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U.H.F. radio echo sounding of Yukon glaciers Narod, Brian Barry 1979

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4 "  U.H.F. BADIO ECHO SOUNDING  OF YUKON GLACIERS  by BRIAN BASRY NAROD B.Sc,  University  of B r i t i s h  Columbia,  1970  13.Sc., U n i v e r s i t y  of B r i t i s h  C o l u m b i a , 1975  A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS  FOR THE DEGREE OF  DOCTOR OF PHILOSOPHY ' in THE FACULTY OF GRADUATE (Department  o f G e o p h y s i c s and Astronomy)  We a c c e p t t h i s to  STUDIES  thesis  the r e q u i r e d  as conforming standard  THE UNIVERSITY OF BRITISH COLUMBIA J u n e , 1979  ((c) B r i a n  Barry  Narod, 1979  In presenting  this thesis in partial  fulfilment of the requirements for  an advanced degree at the University of B r i t i s h Columbia, I agree that the Library shall make it freely available for reference  and  study.  I further agree that permission for extensive copying of this thesis for scholarly purposes may by his representatives.  be granted by the Head of my  Department or  It is understood that copying or publication  of this thesis for financial gain shall not be allowed without wri tten permission.  Department of  GEOPHYSICS & ANSTRONOMY  The University of B r i t i s h Columbia 2075 Wesbrook P l a c e V a n c o u v e r , Canada V6T 1W5  June 25, 1979 Date  my  Frontispiece. An a e r i a l f i s h e y e p h o t o g r a p h t a k e n over the Hazard Glacier. These photographs provide : f l i g h t line control. The surface drainage feature seen in this photograph is v i s i b l e on a g o v e r n m e n t a e r i a l photograph taken at 15,000 m elevation. The l o c a t i o n of t h i s p h o t o g r a p h i s marked by an asterisk on Figure A2.2.  iii  iv  IBST RACT a  high-resolution  freguency  840  of  and m e d i u m - s i z e d compact,  radio  MHz  suppresses  operation  light  out  Territory,  which  valley  aircraft.  of airborne  from  Trapridge  Glaciers.  200  Hazard  cause  i c e c a p s . The  wall  on  Successful  s u r v e y s compare  earlier The  ground-based maximum i c e  Glacier.  scattering  of  field  a  small uses  the and  a  system  simplifies trials  were  Hazard G l a c i e r s ,  Yukon  penetrate  well  with  soundings thickness  ice  depths  on t h e R u s t y  and  encountered  was  Owing t o t h e h i g h o p e r a t i n g  freguency,  from i n h o m o g e n e i t i e s w i t h i n the i c e i s a  of s i g n a l degradation. For t h i s great  thicknesses  S p a t i a l a v e r a g i n g , an moving  echoes  at  sounder  improves  on t h e E u s t y , T r a p r i d g e and  obtained  random  operating  Canada.  Results  m  and  antenna  performance,  carried  sounder  has been d e v e l o p e d f o r s o u n d i n g  polar glaciers  high-gain  from  echo  platform,  of  temperate  immediate reduces  reason the sounder  result  the  major cannot  or debris-rich i c e .  of  effects  operating of  from  a  back-scattered  "clutter. " Results  of ground-based  v a l u e f o r f t a n 8 = 0.26 values.  The  total  been f o u n d t o be  at  received  tests  -50C,  to  antennae  position.  roughness  a t or near the i c e / a i r  coverage The records  in  agreement  power and  very s e n s i t i v e Large  on t h e H a z a r d  small  fluctuations surface,  data t o d e t e c t b i r e f r i n g e n c e results  also  should  be  t h e echo  indicate replaced  that by  Glacier with  power,  a  predicted  d e t a i l s have  (<<I0 cm) in  yield  both  changes  in  caused  by  prevented using  single  in glacier i c e . the  standard  a recording  photographic  medium c a p a b l e o f  V  storing as  more p r e c i s e  magnetic tape  t h e same t i m e  and a c c e s s i b l e d a t a .  A storage  should n o t degrade t h e radar d a t a ,  relieve  a d a t a p r o c e s s i n g burden.  medium  such  and would a t  vi  TABLE OF  CONTENTS  Abstract  -  List  Of  List  Of F i g u r e s  iv  Tables  viii ix  Acknowledgements Chapter  1: I n t r o d u c t i o n  1.1  Background  1.2  Program  1.3  Field  Chapter  xii  2:  1 2  Development  ...  Work  6  A i r b o r n e Sounding  2.1  Instrumentation  2.2  Survey 2.2.1  4  Of G l a c i e r s  ..................  8  Procedure  Flight  8  12  Line Analysis  16  2.3  Results  17  2.4  C o n c l u d i n g Remarks To A i r b o r n e S u r v e y s  24  Chapter  3:  Physical  Properties  Of G l a c i e r s  ................  26  3.1  Experimental Description  26  3.2  Data  27  Analysis  3.2.1  E r r o r s I n Power Measurements  3.2.2  Dielectric  3.2.3  Scattered  3.3  -  28  Attenuation  38  Power D e n s i t y Vs.  Depth  ............  D e t e c t i o n Of L a r g e C o n d u i t S c a t t e r e r s 3.3.1  Theoretical  Patterns For Conduit S c a t t e r e r s  3.3.2  Comparisons  With The  3.4  Field  C o n c l u d i n g Remarks To C h a p t e r  Chapter Future  4.  Concluding  Experiments  Remarks  43 ...-43  Experiments  59  3  And  41  59 Recommendations  For 61  vii  Literature Cited  63  Appendix  67  1; D e t a i l s Of The R a d i o Echo Sounder  A1.1 G e n e r a l D e s c r i p t i o n A1. 1 - 1 System  And O p e r a t i o n  67  Assembly  68  A1.1.2 O p e r a t i o n Of The R a d i o  Echo S o u n d e r  75  A1.2 The T r a n s m i t t e r A1.2.  78  1 Power S u p p l y  ..  79  A1.2.2 M o d u l a t o r  89  A 1.2. 3 The R. F.  Chain  92  A1.3 T h e R e c e i v e r  106  A1.3.1 The R.F. A1.3.1.1 A1.3.  C h a i n And V i d e o A m p l i f i e r  Physical  1.2 C i r c u i t  A i l . 3.2 R e c e i v e r A1.4 The S w i t c h i n g  ..i  107  Decription  107  Description  ,.  Digital Circuitry Regulator  .-  115  Power S u p p l y  138  A1.4.1 P r a c t i c a l C o n s i d e r a t i o n s A 1.4. 2 C i r c u i t A1.5 The C o r n e r A1.5.1 D e s i g n  ..........  Line Appendix  142  Antenna  145  Details  A1.5.2 C a l i b r a t i o n : VSWR Appendix  141  Details  Reflector  2: T r a p r i d g e  Glacier  146 and F o r w a r d G a i n And  Hazard  151  Glacier  Flight  Maps  154  3; D i f f r a c t i o n From A L i n e a r  A3.1 C o o r d i n a t e  Ribbon S c a t t e r e r  Systems  A3.2 The K i r c h h o f f  :  Integral  A3.4 N u m e r i c a l A n a l y s i s Realization  .... 157 157 160  A3.3 N u m e r i c a l R a t i o n a l i z a t i o n  A3.5 P h y s i c a l  108  ... 168 .....  172 ,. 179  Vlll  L I S T OF  TABLES  2.1  System  D e s c r i p t i o n And P a r a m e t e r s  2.2  Compass E r r o r s  18  3.1  Dielectric  39  QJ^notmclukc  L o s s Computation  A1: Power C o n n e c t o r P i n D e s i g n a t i o n s  98  A2: T r a n s m i t t e r : R e q u i r e d  99  A3: T r a n s m i t t e r :  M a j o r Components . . . . . . . . . . . . . . . .  D i s c r e t e Components  Parts L i s t  A4: R e c e i v e r  R.F.  A5: R e c e i v e r  Components: R e q u i r e d  A6: B e c e i v e r  D i s c r e t e Components P a r t s L i s t  A7: S w i t c h i n g A8: F o r w a r d  Module Components  Begulator  Gain  Parts L i s t  Measurement D a t a  Integrated C i r c u i t s  ..........,  100 133 134 135 144 153  ix  LIST OF  FIGURES  Frontispiece  .  i i i  2.1  C o n t i n u o u s Echogram From H a z a r d G l a c i e r . S u r f a c e . .......  2.2  Antenna  2.3  Rusty G l a c i e r . F l i g h t  Line  15  2.4  Rusty  Section  16  2.5  Trapridge  2.6  Hazard  2.7  T r a n s v e r s e S e c t i o n Of H a z a r d G l a c i e r  3.1  S c h e m a t i c Of  3.2  The  36 C o r r e c t e d  R e c o r d s Of  E x p e r i m e n t TX.O  3.3  The  36  R e c o r d s Of  Experiment  3.4  Averages  3.5  R e l a t i v e S c a t t e r e d Power Vs..  Azimuth  (linear)  3.6  Relative  Azimuth  (logarithm)  3.7  Discrete Fourier  3.8  Thermal  3.9  Dielectric  3.10  Installation  Glacier  Aerial  Glacier  Glacier  206  Helicopter  .........  I c e T h i c k n e s s Map  Antenna  Corrected Of TX.O,  TX.9  Scattered  Profile  22  Rotation  Power Vs.  Power V s .  S p e c t r a Of  Experiments  .........  ...  TX.9  31 34 ........  Drill  38  Site  #1  ,.  For Corner  Reflector 45  3.11  Theoretical Rotation  3.12  Rosette Plots  3.13  R o s e t t e P l o t s Of Rosette  Patterns  Of S e l e c t e d  Plots  Selected Of  Data  For Dipole From TX.O  Data From TX.9  Selected  Data  From  Antennae  ....  47  .............  51  .  53  ,. TX.O  After  A z i m u t h a l Smoothing 3.15  Rosette  41 42  Antennae  3.14  35 36  Power  Patterns  29 30  A z i m u t h a l Power  Scattered  Rotation  23  Time  Of H a z a r d G l a c i e r  L o s s e s And  12  20  I c e T h i c k n e s s Map  The  Theoretical  On A B e l l  9  Plots  A z i m u t h a l Smoothing  55 Of  Selected  Data  From  TX.9  After 57  A1.1  B a d i o Echo Sounder B l o c k  A1.2 T r a n s m i t t e r  Diagram  P i c t o r i a l Diagram  A1.3 26 V B e g u l a t o r C i r c u i t  Timer C i r c u i t  A1.5 Power S u p p l y  Wiring  A1.7 T r a n s m i t t e r A1.8 P u l s e  120 MHz  B.  Receiver  Diagram  F.  Circuit  Amplifier  Filter  Amplifier  .. ...  107  Diagram ................... ..............  Characteristic  & Video A m p l i f i e r  Circuit  Speed L o g i c T i m i n g Logic Timing  Diagram  109 111 112  Diagram  114  L o g i c Diagram ....................,  A1.20 H i g h Speed L o g i c ; C i r c u i t  A1.22 H i g h Speed  Diagram .,  Bandpass C h a r a c t e r i s t i c  Speed L o g i c ;  A1.21 H i g h  Circuit  94  Diagram  F.  High  Diagram  93  97  A1.16 I .  A1.19  Diagram . . . . . . . .  B l o c k Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . .  Module C o n n e c t i o n  A1.18 Power S u p p l y  Circuit  91  96  F.  F.  ....................  .,-  Pictorial  I.  85  90  Diagram  A1.15 B.  A 1.17 L o g .  Diagram . . . . . . . . . . . . . . . .  87  Oscillator-Amplifier  A'1.13 T r a n s m i t t e r A1.14  81 84  Schematic  Circuit  A1.11 x6, x7 M u l t i p l i e r s A1. 12 840 MHz  Diagram  I n t e r n a l Layout  Amplifier  79 80  Diagram  A1.9 C a t h o d e M o d u l a t o r C i r c u i t A1.10  ........................  Diagram  A1.4 Power S u p p l y  A1.6 Power S u p p l y D r i v e r  69  117  ...118  Diagram  1  119  Diagram  2 ...................  122  A-1.23 Low  Speed L o g i c ; L o g i c D i a g r a m  123  A1.24 Low  Speed L o g i c ; C i r c u i t  125  A 1.25 Low  Speed L o g i c  Timing.Diagram 1 ....................  126  A1.26 Low  Speed L o g i c T i m i n g D i a g r a m 2 . . . . . . . . . . . . . . . . . . . .  128  A1.,27 Low  Speed L o g i c  129  A1.28 F r o n t  Diagram  Timing Diagram  Panel Display;  Circuit  3  Diagram  131  xi  A1.29 R e c e i v e r C o n n e c t i o n Diagram . . . . . . . . . . . . . . . . . . . . . . . . .  132  A1.30  S w i t c h i n g R e g u l a t o r B l o c k Diagram  139  A1.31  Switching Regulator C i r c u i t  141  Diagram  A1.32 C o r n e r R e f l e c t o r  G a i n Vs.  A1.33 C o r n e r R e f l e c t o r  Impedance Vs.  A1.34 The C o r n e r R e f l e c t o r A 1.35 T h e o r e t i c a l  Patterns  Spacing  ..................  Spacing  .............  Antenna For  Various  Corner  Reflector 150  A1.36  A-scope  A2.1  Trapridge  Echogram O v e r K l u a n e Lake G l a c i e r Composite  Map  152 Of C o n t r o l l e d  Lines  Flight «... . 155  A2.2 H a z a r d G l a c i e r  A3.1  146 148  Antennae  Lines  146  Composite  Map  Of  Controlled  Flight  ..................................................156  P i c t o r i a l Of S c a t t e r i n g C o o r d i n a t e S y s t e m s . . . . . . . . . . .  A3.2 K i r c h h o f f  Diffraction:  A3.3 T y p i c a l F u n c t i o n  158  P i c t o r i a l Of N u m e r i c a l Model .. 173  J For Corner R e f l e c t o r  Antennae  ..... 178  xii  ACKNOWLEDGEMENTS I  wish to thank  project the  and  field I  Committee  his  f o r h i s invaluable assistance during  thank  the  National  Canada  on A r c t i c  system  grants  and  67-3479  work  conducting Research  to  University  be  Station  the I n s t i t u t e  field  seasons.)  support.  by N a t i o n a l  undertaken  P.  of  surveys  in  Kluane  we  were  the Arctic  forlogistic  support  based  at  D r . S. G. C o l l i n s  a s s i s t a n c e d u r i n g t h e 1976 f i e l d U.B.C. c o m p u t i n g  allowing  the  While Kluane  extending  and J .  G.  over  {I  many  t h e 1975 Yukon Napoleoni  for  work.  c e n t r e s u p p o r t e d the p r o d u c t i o n o f t h e  typescript. thank  with  o f North America;  Cary f o r h i s a s s i s t a n c e during  their  I  Council  N a t i o n a l Park.  Institute  t e s t . I thank  thesis  Research  t o P a r k s Canada f o r  field  The  Canada,  and A l p i n e . R e s e a r c h f o r f i n a n c i a l was f i n a n c e d  of  of  Columbia  the a e r i a l  thank  Council  and 67-3809. Dr R. H. Goodman was g e n e r o u s  thank  I  a l l phases o f  British  development  the  Research  t i m e and a d v i c e . I am g r a t e f u l  this  f o r h i s support of t h i s  trials.  Environment  The  Dr. G. K. C. C l a r k e  D r . E. H u t c h i n g s f o r h i s e d i t o r i a l  assistance.  1  CHAPTER J : This  INTRODUCTION  t h e s i s i s concerned with t h e development  Freguency ice  (UHF)  radars  m a s s e s . The work r e p o r t e d  U.B.C. o f an 840 MHz tests  made d u r i n g This  sounding the  as w e l l  field  radio  echo  includes  2  1 i s a complete  Chapter  3  use t h e s o u n d e r structures. improve  future  expected  i n the Canadian  describes  echo  glaciers  sounder  the  i c e caps o f the A r c t i c  did  not  technique  Ice  of airborne of  fabric  the  echo and at  tests. system..  of attempts t o  and  the r e s u l t s  primarily  intraglacial  and c o n s i d e r s  the  how  desire  typically  interest  were t h e  A r c h i p e l a g o , although our f i e l d  work  flow  area.  Elias  to  and  i c e caps, that  Valley  characteristics we  also  physical  p r o p e r t i e s such  ( C l o u g h , 1977; H a r r i s o n , properties  the  Mountains,  latter  glacial  by  of p a r t i c u l a r  the d i s t r i b u t i o n s of scattering  fabric  field  UHF  optimized f o r i c e depths  f o r monitoring t h e i r included  at  developed  the r e s u l t s  of the n o r t h e r n S t .  different  studied  to  radar  description  ice  Arctic,  valley  systems  background  the  3 describes  cold  sufficiently  development  o f t h e p r o j e c t development  was m o t i v a t e d  a radio  and  brief  4 summarizes  develop  include  polar  experiments.  This research  interest  a  t o study g l a c i e r  Chapter  sounding  season.  technical  with Appendix  High  and t h e r e s u l t s o f  w e l l a s t h e p r o c e d u r e s and r e s u l t s  Appendix  commonly  sounder  as a d e s c r i p t i o n  work. C h a p t e r  o f echo  here i n c l u d e s the  t h e . 1976 f i e l d  chapter  U.B.C. as  to  f o r the purpose  of Ultra  included  wished  glaciers  have  from  more  to  the  develop  a  properties.  Features of  as bedrock  roughness,  objects,  l a y e r s and c o n d u i t  1973; Smith and possible  Evans,  strain  1972).  alignment of  2  optical  axes  (Campbell, A  and  stress  induced  optical(R.F.)  and O r a n g e , 1974; J o h a r i , a n d J o n e s ,  high  resolution  measurement potential  capability  UHF  radar  offered  f o r Arctic  sensitivity  to  of  gain  aperture  make a  variations  radar in  longer  to  as  those  A of  the execution  caused  intraglacial  a  of g l a c i e r s .  make p o s s i b l e t h e u s e  effects  roughness,  p r o p e r t i e s than  instrumentation  most t i m e - c o n s u m i n g primarily  by  20 cm  smaller  s t r u c t u r e s , and  variations detectable  For  and o p e r a t i n g  results  design  parts of t h i s  glaciological.  description  radio  well  at  wavelengths.  Although  The  an i c e d e p t h  A w a v e l e n g t h i n i c e o f about  sensitive  bedrock  crystallographic  as  a n t e n n a e as w e l l a s s i m p l i f y i n g  most s u r f a c e e x p e r i m e n t s .  would  both  properties  w a v e l e n g t h i n a i r o f a b o u t 30 cm would high  1975).  glaciers  physical  anisotropy  presented  and d e v e l o p m e n t  research, the. motivation  this  reason  the detailed  manual a r e r e l e g a t e d t o t h e here  demonstrate  echo sounders f o r t h e study  were t h e was  system  appendix.  the u s e f u l n e s s  o f UHF  of glaciers.  1.1 BACKGROUND The in  behaviour  large  sheets, Waite  relatively  echo sounding  dielectric limited  (300 MHz-3 GHz) e l e c t r o m a g n e t i c  i c e masses and t h e u t i l i t y  have r e c e i v e d radio  of UHF  little  the  usefulness  the f i r s t (1966),  regions  using  investigation  i n t h e l o w e r VHF  l o s s e s and h i g h e r  an  o f UHF r a d i o echo  of of  UHF  sounding  compared  (30-300 MHz) band.  susceptibility sounders  extensive  to on  radio  waves  with  Greater  scattering  have  large polar i c e echo  SCR-718 440 MHz a i r c r a f t  sounding.  altimeter i n  3  northwest 400  Greenland, reported  loss  of s i g n a l a t depths exceeding  m. VHF s o u n d e r s have, no d i f f i c u l t y  this  thickness.  valley-wall than the  On  small  reflections  i c e penetration small  size  .and  and  s o u n d i n g i c e many  medium-sized  aircraft  valley  times  glaciers,  man-oeuvrability,  rather  d e p t h , a r e t h e main c o n s i d e r a t i o n s ;  and  directivity  of  DHF  antennae  thus  become  attractiveIn  1970 on R o s l i n G l e t s c h e r ,  D a v i s and o t h e r s (1973>  UHF s o u n d e r  t o measure i c e t h i c k n e s s e s i n a c o l d  Man-hauling  a modified  measure  SCR 718 r a d i o  i c e thicknesses  up  using  t h e SCR 718 had been  that  scattered  returns  identification Evans,  a  sounder  first  t h e y were a b l e t o  400 m; a l l p r e v i o u s s o u n d i n g s  made on p o l a r i c e c a p s . They at  many  distinct  locations  bottom  hauled  UHF r a d a r  designed  echo  reported  often  difficult  strictly  was a 620 MHz i n s t r u m e n t b u i l t  Environment  o f Canada  as  made  ( S m i t h and  an  the  DOEC  (DOEC) by Goodman  system  VHF s y s t e m s ,  varying  bedrock  sounder's  performance.  have  made  was  and t h a t  of  valley  wall  did  not  identification  of the  finer  demonstrated  resolution  echoes  and  seriously  of a distinct  than  rapidly  affect  As with t h e SCR 718, i n t e r n a l  the  depth  ( 1 9 7 5 ) . R e s u l t s o f man-  capable  topography  ice  f o r t h e Department  s u r v e y s of t h e Rusty and T r a p r i d g e G l a c i e r s  existing  could  glacier.  1972).  The  that  of  to  altimeter  valley  used, a  the  scatterers bottom  echo  ambiguous. Sondergaard have  reported  Greenland  and Skou some  (1976) u s i n g  successes  with  a 6  Kw,  airborne  300  MHz  radar  sounding  of the  I c e Cap, however as an i c e d e p t h measurement  tool  i t  4  lacks the penetration Bogorodskii limit  of about  has  use  in  increase  with a range  of a radio  (DHF) band  sounder  t o o p e r a t e on s m a l l We c h o s e  as the centre  dielectric  echo  840 MHz i n t h e u l t r a  frequency  losses  the small  Most C a n a d i a n  w i t h i n t h e maximum The  size  and  system  the system  range  specifications of  antennae,  intervalometer  were  d e s i g n and f a b r i c a t i o n New J e r s e y ,  i c e masses  for  random  in  the  took p l a c e 1974,  sounder  power  in  a l l designed were c o m p l e t e d  completed spring  airborne to  be  U.B.C.  completed the  first  o f 1975. The  intercom  at  of  (Narod, u n p u b l i s h e d ) *  the  supply,  much  expected  a t U.B.C. We  and  several  scattering  simplifies  are  o f an UHF s o u n d e r  development  version  receiver,  o f an DHF a n t e n n a  polar  for  glaciers  w i t h f r e q u e n c y , a high^-gain. a n t e n n a c a n o f f s e t  operation.  and  camera  The t r a n s m i t t e r  by Microwave  Control  Co.,  U.S.A.  proposed s e v e r a l experiments, each designed t o t e s t t h e  capability two  MHz s y s t e m  1979).  Canada. The need  Although  loss;  working  700  the sounder's p r o p e r t i e s .  reasons.  system.  DEVELOPMENT  northern  higi. frequency  We  a  1973 we began d e v e l o p m e n t  dictated  the  60 MHz  operated  300 m ( B e n t l e y ,  1.2 PEOGEAM In  of t h e i r  and l i m i t a t i o n s  antennae  birefringence  on in  the  a  o f . t h e new s o u n d e r .  glacier  glacier  wavelength  (20 cm i n i c e ) would  relatively  s m a l l antennae  Using  a  single  surface i c e . We  antenna  felt  facilitate  (1.5 m) would  .we  By  hoped that  to the  with detect short  t h i s t e s t because t h e  be e a s i l y  we p r o p o s e d  working  manipulated.  t o o p e r a t e the system  5  from  light  aircraft.  sounder's a b i l i t y other  aspects  interfering with  of these  effects  where  Photographic The Athabasca early  data  returning  p o l a r and  would be  field  temperate i c e .  the d e t e r m i n a t i o n  Two  of  the  in  valleys  small  flight  took  Alberta,  before  the  the problems a s s o c i a t e d  line  place  of the  we  and  other  for a l l tests. in  May,  The  1975  test  was  transmitter  observed  in  control i s necessary.  used  Canada.  of a f a i l u r e  not  measure  w a l l s , and  were t o be  trial  would  a  on  terminated  high  very  the  voltage  high  level  of  s c a t t e r e d power.  Further July,  surveys  precise  Glacier,  but  both  tests  records  as a r e s u l t  supply,  tests  of valley  very  first  flight  to penetrate  operating a e r i a l  areas  preliminary field  i n the  St.  Results of tests prompted  Elias carried  modifications  trigger circuit. 500  These  The  Mountains, o u t on to  the  These  resulted  flight  p l a c e d u r i n g June  Yukon  Territory,  a n t e n n a e and  tests  1975  took  the s u r f a c e o f  Airborne  helicopter.  amplifier.  trials  were c a r r i e d  tests  and  Canada.  the R u s t y  Glacier  t o the t r a n s m i t t e r out  from  a  Hughes  i n m o d i f i c a t i o n s to the were made w i t h o u t  video  flight  line  control. A  final  place in early from  a  c a m e r a . The  internal  180  with the  the f l i g h t  check,  August, i n the  Cessna  performed line  flight  was  i n c l u d e d passes  to the  a  successful  r a d a r , a new simply over  e c h o e s were d e t e c t e d .  1976  field  work,  V a n c o u v e r , Canada a r e a .  aircraft  modified test  prior  and  a h a r d w a r e c h e c k , and  several  Operating  systems check  intercom  temperate  took  a  was  flight although  glaciers  no  6  1.3 FIELD WORK  In Elias two  1976 we t e s t e d  August  Mountains,  forms, The  Yukon  airborne  airborne  glaciers  t h e sounder  Territory,  sounding,  Trapridge,  experiments  took  t h e t h e r m a l regime  number o f s i t e s ;  a network o f  control  To g e t s i m i l a r  points.  we s e t up a f i e l d  ice  The the  camp  at  experiments  involved  vertical  f o r one  axis  orientations.  the  scattering  for  These  is  Hazard  and  hence  Glacier  noting would  a  the  provided  ground  Hazard  Glacier  levelling  i n August,  work  using  survey,  drilling  and  a Bell  206  surveys of t h e s e : g l a c i e r s .  drill  two  #1  site a  place  orthogonal were  here t h a t  guality  of  2) .  antenna  These  about  transmitter  a  antenna  designed t o recover the from  scattering  would  provide information  objects  depolarization  due  to  1963).  the i n s t a n t  allow  a t o u r camp on  (Appendix  receiver  The e l l i p s e s  not  three  t h e R u s t y and  with the r a d a r , hot-water  (Beckmann and S p i z z i c h i n o ,  data r e c o r d i n g  field,  out  w i t h i n t h e i c e and a b o u t  worth  on  were known a t a  i n f o r m a t i o n about  experiments  bedrock.  anisotropy  It  markers  of p o l a r i z a t o n of r e f l e c t i o n s  from  about  and i c e d e p t h  survey  rotating of  took  experiments.  primarily  p h y s i c s experiments took  Glacier  work  Extensive g l a c i o l o g i c a l  carried  we d i d t h e a e r i a l  Hazard  and  place  measurements. L a t e r  glacier  ellipses  and  experiments  temperature  helicopter,  physics  been done on two o f t h e s e g l a c i e r s ,  so  ground-based  Canada. The f i e l d  and g l a c i e r  i n t h e S t e e l e Creek b a s i n .  had p r e v i o u s l y  on g l a c i e r s i n t h e S t .  for  any  photography analysis  in  used the  t h e data gathered from t h e  s u r f a c e c o u l d n o t be e f f e c t i v e l y  judged  there.  7  On  the  other  successful  at  There  task  the  a f a r simpler (1975)  has  two-fold. recording Also,  data  quality  r e q u i r e d the  task than  analysing  f o r using  broadband  is  entire  difficulty  data  both  investigators recording  were g u i d e d  frame  an  by  airborne  tests.  had 1975;  t o some e x t e n t  waveform. with  frame  echo, Oswald  which he. used  by  photography  was  technique  for  acquired  continuously  (Sobin,  very  analyses.  easily  have  the  was  d e t e c t i o n of a bedrock an  the  photography  during  records f o r s t a t i s t i c a l  Photography  photographic  instant  mainly  motivation  other  1 9 7 6 ) . We  indicating  the  a l s o commented on  photographic The  hand,  a  and  instantaneously.  long h i s t o r y  Gudmandsen their  of  and  experience.  using  others,  8  CHAPTER 2: AIRBGfiNE The sounder, been and  SGUNDMG OF GLACIERS  University which  of  d e s i g n e d t o sound  frequency  of  the  ease  and i i g h e r  dielectric  the  echograms d e m o n s t r a t e changes  moving  highly  returns  The  system  over  that  to internal  antenna  and  the  returns vary g r e a t l y  (Bailey  can  and o t h e r s ,  recording, be  rapidly  1 9 6 4 ) . By  (Fig..2.1) the  identified When to  be  with  among  the  airborne,  the  visible  on  an  phosphor.  UBC  echo  antenna  system  Appendix  (transmitter, two-way  and  b u t t h e s e drawbacks a r e  returns.  too  glaciers  INSTRUMENTATION  circulator, relevant  vary  has  i s made a i r b o r n e . S u r f a c e  while continuously echo  40 MHz  of the  system  .variable . scattering  oscilloscope  size  position  polar  susceptibility  scattering  c o n s t a n t bottom  scattering  2.1  that  i n antenna  t h e antenna  relatively  entire  system,  i n frequency  losses,  by t h e h i g h g a i n and s m a l l which  DOEC  bandwidth  i s 124 dB. The 35% i n c r e a s e  with  minute  840 MHz,  the  echo  (Narod, u n p u b l i s h e d ) . I t s  DOEC s y s t e m b r i n q s i n c r e a s e d  scattering offset  i s  (UBC) r a d i o  the smaller  i c e c a p s f o u n d i n n o r t h e r n Canada  performance  is  Columbia  i s s i m i l a r i n concept to  specifically  centre  in  British  sounder  parameters; complete  receiver  155 dB. Both  gain the  a transmitter,  and o s c i l l o s c o p e d i s p l a y .  1. The system  antenna  comprises  2.1  lists  system d e t a i l s a r e i n c l u d e d  performance  and c i r c u l a t o r )  o f the radar t r a n s c e i v e r is  124 dB.  o f 31 dB, t h e e f f e c t i v e transmitter  Table  receiver,  and  system  receiver  are  Adding  the  performance internally  Figure  2.1 A C o n t i n u o u s Echogram From H a z a r d  Glacier  Surface  A c o n t i n u o u s echogram t a k e n on t h e s u r f a c e , n e a r d r i l l s i t e 1 on H a z a r d Glacier, showing significant scattered power r e t u r n i n g b o t h b e f o r e and a f t e r t h e d o m i n a n t b o t t o m echo. This record was made by r o t a t i n g t h e a n t e n n a 360<> a r o u n d a v e r t i c a l a x i s . The b i t code a t the l e f t i s a system-generated data i d e n t i f i e r (see A p p e n d i x 1 . 3 ) .  protected failures.  against A  120 hHz  abnormal signal  power from  surges a  crystal  caused  by  oscillator  cable is  10 Table  2.1  System D e s c r i p t i o n , And  Parameters  T r a n s m i t t e r : G a t e d d u a l microwave c a v i t y t r i o d e F r e q u e n c y i s s e t by c r y s t a l . Power Pulse length R i s e time F a l l time Receiver:  4.1 Kw 50 ns 18 ns 28 ns  & rate  Thin f i l m s o l i d response.  T/R  peak rms (+66 a t 10 KHz  state hybrid.  Bandwidth Intermediate frequency Dynamic r a n g e Sensitivity System l o s s e s (including Switch: Isolation 1 dB B a n d w i d t h  amplifier.  Logarithmic  40 MHz 120 MHz 80 dB -70 dBm 12 dB I.F. conversion  1 dB B a n d w i d t h VSWR Forward g a i n Depth Width Length Weight  multiplied oscillator then  system  and  720  is a  to  protected  MHz dB m m m  ±  1  and  840  MHz  to  dB  provide  frequencies respectively.  gated  and  three-port  operate by  MHz  carrier  amplified,  circulator  >40 1.14 15.5 0.30 0.59 1.18 9 Kg  parasitic  T o t a l system weight 50 Kg Power r e g u i r e d 28V 5) 10A E s t i m a t e d maximum r a n g e i n c o l d i c e 650  to  with  isolated ferrite  at  limiter.  device  The  The  the  a s i n g l e a n t e n n a . The  a solid-state  loss)  Passive c i r c u l a t o r 25 dB >40 MHz  A n t e n n a : Two d i p o l e c o l i a e a r a r r a y w i t h a t h i r d e l e m e n t and a 90° c o r n e r r e f l e c t o r .  General:  dBm)  4 Kw  which  m  the  local  carrier  is  level.  The  allows  the  receiver input i s  signal i s  converted  to  11  the  120  I.F.  MHz  intermediate  amplifier-detector  characteristic The dipole  with  antenna  u s e f u l dynamic range  forward  to  the  August  a  and The  H-plane h a l f  1976  flights  we  intensity  in  vertical  input one  scan  data.  and  This  from  the  18<>  The  operator  a Polaroid-backed in  replaced  by a  through  such  our the  oscilloscope  approximately  phosphor  A slow ramp full  camera  20%  the  records  dead t i m e .  recording  on  screen  controls  system  m a g n e t i c r e c o r d e r o r g r a p h i c r e c o r d e r and  developing  On  from  the  manually  photographic  and  attached  the  oscilloscope.  minute.  The  (Fig..2.2).  r e c e i v e r modulates  trace  results  skid  antenna  installation  the  t h a t i n f u t u r e the  As  driven  15.5±1.0 dB.  high  the  scans  recommend  2.2  gain i s  w i t h two  power beamwidths a r e  outrigged  of a T e k t r o n i x model 475  vertical  reflector  h e l i c o p t e r with  i n an e x p e r i m e n t a l output  dB.  gear.  any  video  of 80  The  response  be  hook o f  The  filtered.  a n t e n n a i s compact enough t o  cargo  helicopter,  height  is  E-plane  and  logarithmic  e l e m e n t s . I t s measured  respectively.  fact,  a  corner  44°  the  has  90°  estimated  the  a  frequency  are,  (We be in  a system.)  SURVEY PROCEDURE w e l l as  sounding clearance.  Overleaf: installed  data The  the  arrival  time  of  the  r e q u i r e knowledge o f a i r c r a f t UBC  sounder,  Figure 2.2. on a B e l l 206  when  used  The UBC radio helicopter.  bed  echo,  p o s i t i o n and as  echo  its  own  sounder  useful ground radio  antenna  12  13  altimeter,  receives  a  strong  echo f r o m  n e c e s s a r y , however, t o f l y a t l e a s t in  order  received  to  separate  pulse.  cause t h i s  The s m a l l  limitation,  t h e minimum r e q u i r e d surface.  to control  above a  the p i l o t  greater  dynamic r a n g e  elevation  as  c a n use v i s u a l  h i s elevation  surface; poor  are  references  and  the  film  reduce  the i c e  surface  (survey  as  markers,  and m a i n t a i n a c o n s t a n t c l e a r a n c e  ratio  of the l a t t e r  procedure i s  (Swithinbank,  1968) .  Its  s e v e r a l : reduced a i r speed, reduced a c c u r a c y  photography—-not  s i c k n e s s and i n c r e a s e d were c o l l e c t e d  d a t a from  surface  could  t h a n 25 m a b o v e to  Iti s  from t h e f i r s t  o f t h e phosphor  c o n s t a n t h e i g h t above t h e  we have e s t i m a t e d our low l e v e l  Glacier  pulse  close  cannot m a i n t a i n a p e r f e c t l y  flight-line  ice  r e c o r d i n g system  to l e s s  flying  signal-to-noise  (the p i l o t  and  transmitted  t h e i c e s u r f a c e . The a d v a n t a g e  disadvantages  air  40 m a b o v e . t h e  An i m p r o v e d  Alternately,  possible, etc.)  the  the i c e s u r f a c e .  risk  the Trapridge Glacier  low e l e v a t i o n s ;  d a t a from  t o mention  of  from h i g h  height  at  discomfort  crashing.  elevation  Data  (Figs.  were c o l l e c t e d the Hazard  6±2 m)  due t o  for  Busty  2.3 and 2 . 4 ) ;  from  Glacier  and  both  were  high  collected  o n l y a t low e l e v a t i o n . For  flight  reckoning aircraft  and  airspeeds,  records  aerial  intercom  collection.  was  and v i s u a l  collection. when  fisheye  we  used  photography. -verbally  Navigation  210°-coverage  which,  line  A  tape  included Aerial  l e n s was a l s o  Our i n t e n t i o n  combination  was t o t a k e  compared t o l a r g e - s c a l e  of  recording  synchronized  information references.  a  with  dead of the  the  data  compass h e a d i n g s ,  photography  with  a  s y n c h r o n i z e d with t h e data photographs  every  10 s,  p h o t o g r a p h s , would p r o v i d e  14  locations  and  photographic behaviour  flight  of the  vibrations aerial  these  values  incomplete  now  camera  due  to  caused  been r e p l a c e d  by  glacier  by a 70  about  to  change  airspeed  accuracy  relatively  be  referenced  1 s e c o n d . With t y p i c a l  m s *) -  on  Trapridge  l e s s than  50  the  of  and  aircraft  several  slowly,  to the  airspeeds  H a z a r d G l a c i e r and  G l a c i e r along-path  mm  Vinten  heading  seconds.  of  Since  more p r e c i s e t i m i n g  data  with 40-60  an  can  is  located  in  accuracy  of  Km  hr~*  R u s t y G l a c i e r and  plan accuracy  are  be  (10-  less kept  on to  m.  Across-path  Overleaf; in Figure  aircraft  ANALYSIS  a timing  can  erratic  camera).  references with  was  Unfortunately  n e e d e d . R e f e r e n c e s t o v i s u a l c u e s s u c h as s t a k e s  the-  the  camera has  FLIGHT LINE  recoverable  15  control  reconnaissance  Verbal  (frontispiece).  m o t o r - d r i v e n Nikon  (the  2.2.1  not  headings  dead r e c k o n i n g  F i g u r e 2.3. The 2.4. The r e g i o n  tolerances  are  determined  by  the  f l i g h t path o f the p r o f i l e reproduced shown i s a t 6 1 ° 1 5 ' N , 140O20«W.  Second o v e r l e a f : F i g u r e 2.4. C r o s s - s e c t i o n of the Rusty G l a c i e r s h o w i n g p h o t o g r a p h i c a l l y - r e c o r d e d d a t a . The s m a l l c i r c l e s a t t h e i c e s u r f a c e r e p r e s e n t the c e n t r e l i n e s u r v e y s t a k e s . The larger c i r c l e s a t the bedrock boundary i n d i c a t e the i c e depths measured with the DOEC system (Clarke and Goodman, 1975). V e r t i c a l e x a g g e r a t i o n i s 4 : 1 . The d a t a r e c o r d s show c l e a r separation of the transmitted pulse, ice s u r f a c e r e f l e c t i o n and i c e b o t t o m r e f l e c t i o n , e v e n o v e r i c e as t h i n a s 30 m. The dark vertical bars are synchronizing marks with the 35 mm camera o r w i t h v e r b a l c u e s r e c o r d e d on t h e f l i g h t r e c o r d e r . The v e r t i c a l scale is 500 n s d i v i s i o n . D a t a f o r t h e c r o s s - s e c t i o n were c o m p i l e d f r o m two p a s s e s o f i d e n t i c a l p l a n and o v e r l a p p i n g profile (one n o t shown). - 1  16  NOI1VA313  17  accuracy  of  referred  from  apparent and  compass the  and  visual  aircraft  plotted  on a e r i a l  i n f o r m a t i o n . T h i s d i f f e r e n c e can possible  aircraft  deviation  Magnetized  were  introduce  to  match  parallax-affected  published  our large  maps  scale  of  the  However,  accepted  the  references.  best q u a l i t y  approximately We  50  and at  10  m m  These  2.3  RESULTS  The  profile except  the lower end,  Values  photos.  from  airline.  refers  our  system  to  Cartesian  photo  well  with  dead  tied  and  to  error  respect refers  enlargement  are  for  (isolator  coordinate  photographic  50  2.2).  Distortion . error  lines  headings  considering  error  the a e r i a l  area.  an  f o r by  sounder  survey  to  optics. to  visual  reckoning . has  m.  line  c o n t r o l came f r o m  photographs  provided  (the d r a i n a g e f e a t u r e i n t h e  the  fisheye  tie  points  frontispiece  across).  have e s t i m a t e d o u r o v e r a l l  m f o r accepted  2.4,  flight  photography. 10  than  found  the c h a r t e r i n g  Rosette  Across path plan accuracy  a c c u r a t e t o about is  by  aerial  flight  been e s t i m a t e d a t b e t t e r  line  (Table  echo  to orient  We  were  using a l l available  accounted  error  ground  i n t r o d u c e d by  flight  be  provided  nonlinearities  The  photographs  deviation.  r e f e r s t o our i n a b i l i t y to  of  compass.  12° between o b s e r v e d  m a t e r i a l s i n the r a d i o  circulator) inability  sources  r e f e r e n c e s . Headings  magnetic  systematic discrepancy of  headings  several  cue  plan accuracy a t better  than  data.  of the Rusty f o r crossing follows  Glacier  presented i n  the terminus of the  the c e n t r e l i n e  of survey  Figures Backe  2.3  Glacier  m a r k e r s down  18  Table  2.2 Compass  Errors  Typical  To  Be E x p l a i n e d  Aircraft  .12°  Deviation  Introduced  2°  5° 3°  Error  Distortion Reading  5°  Deviation*  Rosette Error Cartesian  Maximum  4°  Error  1"  Error  5°  * T e s t s f o r t h i s v a l u e were p e r f o r m e d i n V a n c o u v e r , C a n a d a . The s u r v e y a r e a was much f u r t h e r n o r t h , p o s s i b l y w i t h i n t h e a r e a o f compass u n r e l i a b i l i t y . The a c t u a l v a l u e t h u s may be l a r g e r . .  the  g l a c i e r . The p r o f i l e  i s  in  excellent  earlier  survey  Goodman,  1975). F o r r e a d y c o m p a r i s o n  taken ice.  the 10  made by m a n - h a u l i n g t h e DOEC s y s t e m  176 m u s  as  - 1  the  s y s t e m . The r e m a i n i n g t h r e e m,  have  been  attributed or  to  ground  survey  could  yield  larger  area of t h e bedrock.  The echo  Rusty  implying  Resolution  comparison within  to a deviation  possible  shallower  Glacier profile  sounder.  work  of that  have  waves i n  i s  possible  a l l less  than  interpretation the airborne  path of  system  i t illuminates a  demonstrates s e v e r a l 4m  we  o f the f l i g h t  i c e , since  (about  an  the r e s o l u t i o n of  discrepancies,  difficulties  data. I t i s also data  this  with  ( C l a r k e and  v e l o c i t y of electromagnetic  o f t h e measured i c e d e p t h s a g r e e  near t h e headwall,  the  with  At t h e t e n l o c a t i o n s where d i r e c t  seven  agreement  or  features  one-tenth  of of a  19  graticule  division)  i s currently  limited  recording  scheme. The a v e r a g i n g e f f e c t  suppresses  scattering  accumulated Data  were c o m p i l e d  the  two  days,  Glacier.  from t h r e e of t h e f o u r  resulting  The T r a p r i d g e G l a c i e r  Again,  i t i s  where  thickness  There  possible  limit  were n o t i n d i c a t e d from  may s p l i t ridge  also  as to  than  during on t h e  has an a r r a y o f s u r v e y  visual  compare  navigation the  aids.  airborne i c e  of the present airborne  by t h e ground  good,  system.  t o w a r d s an i c e f a l l .  half  way up t h e g l a c i e r ,  T h i s zone o f s h a l l o w  i n t o two s e p a r a t e dynamic z o n e s .  which s p l i t s t h e t e r m i n u s of  survey data. A shallow r i b  t h e n o r t h e r n edge, a b o u t  the glacier  between  headwall.  made  a r e a number o f f e a t u r e s i n t h e new i c e t h i c k n e s s map  across the g l a c i e r  found  flights  (Goodman and o t h e r s , 1975) , agreement i s v e r y  within the resolution  one-third  by t h e  measurements w i t h t h o s e made from t h e s u r f a c e w i t h t h e  DOEC s y s t e m  rock  i s exposed  i n more e x t e n s i v e c o v e r a g e  during the f l i g h t s  extends  grain  film  1000 t r a n s m i t t e r p u l s e s .  markers u s e f u l  that  photographic  f o r t h e i c e t h i c k n e s s map o f T r a p r i d g e G l a c i e r ( F i g .  2.5)  Busty  the  o f the photographic  r e t u r n s s i n c e each  output o f over  by  extends  t h e -way  up t h e g l a c i e r .  t h e . two  rock  spurs  The m a j o r  under t h e i c e about  A b a s i n o f i c e h a s been  near  The new f e a t u r e s a r e c o n s i s t e n t  ice  the  centre  w i t h t h e ground  of  the  survey  O v e r l e a f : F i g u r e 2.5. T r a p r i d g e G l a c i e r i c e t h i c k n e s s map.. The contours a r e computer generated by i n t e r p o l a t i n g from t h e a i r b o r n e d a t a o n t o an a r b i t r a r y s q u a r e g r i d . The interpolation u s e s an i n v e r s e ^ - d i s t a n c e - s q u a r e d w e i g h t e d a v e r a g e , o f t h e n e a r e s t datum i n each o f e i g h t e g u a l s e c t o r s . I n r e g i o n s o f low d e n s i t y c o v e r a g e and p a r t i c u l a r l y near t h e southwest h e a d w a l l , t h e map r e f l e c t s t h e a r b i t r a r y n a t u r e o f t h e i n t e r p o l a t i o n scheme.  20  21  data  and  airborne  results  of  the  more e x t e n s i v e c o v e r a g e  of  most s e r i o u s l i m i t a t i o n  of the  sounder i s i t s i n a b i l i t y  p e n e t r a t e great t h i c k n e s s e s of temperate or d e b r i s - r i c h  We  believe  the  i c e t h i c k n e s s map  o f Hazard  owes much o f i t s c h a r a c t e r t o an i n t e r n a l by  the  merging  shows, a l o n g of  of the  the  relatively  ledge  constant  believe that i n this More  internal The  rise  from  northern  likely  moraine  flight the  edge o f t h e  (60-80 m)  a t o r t u o u s 80 r e g i o n we the  moraine  glacier,  i c e depth.  layer  a  shallow  The  boundary  m i c e depth  radiation  (Fig.  main t r i b u t a r i e s .  have a c t u a l l y  f o r an i n t e r n a l line  yielded  "deeper" southern  ledge  two  Glacier  has  ice.  contour.  2.6)  formed The  map  ledge  We  of  the  do  not  measured t o t a l  ice  been s c a t t e r e d by  the  layer.  evidence  transverse  glacier's  northern  i s d e f i n e d by  depth.  our  programme.  The to  are  ( F i g . 2.7).  reflector data  These very  O v e r l e a f : F i g u r e 2.6. H a z a r d c o n t o u r i n t e r v a l i s 20 m. The shaded a r e a .  two-fold.  Each  showing an e x t r e m e l y  steep  region of  is  the  glacier  s t r o n g boundary  to points  the do  Glacier ice thickness map. The major m e d i a l m o r a i n e i s shown a s a  Second o v e r l e a f : F i g u r e 2.7. A t r a n s v e r s e s e c t i o n o f t h e H a z a r d G l a c i e r s h o w i n g t h e i n t e r p r e t a t i o n and a reproduction of the data. The c r o s s - s e c t i o n i s shown l o o k i n g u p - g l a c i e r , w i t h t h e n o r t h e r n b o u n d a r y t o t h e r i g h t . The s o l i d line represents the first interpretation of the d a t a . . The f l i g h t l i n e shown on F i g u r e 2.6, went from the northern boundary to the southern boundary. The steep r i s e c o i n c i d e s w i t h the edge o f t h e m a j o r m e d i a l m o r a i n e . The s h a l l o w l e d g e d e p i c t e d by the solid line above a s h a d e d band i s p r o b a b l y . n o t b e d r o c k b u t a d e b r i s l a y e r , p e r h a p s b r o u g h t w i t h o v e r l a i n i c e from t h e n o r t h e r n arm of the glacier. The dashed line represents a h y p o t h e t i c a l bedrock surface.  23  24  not  define  a  tortuous  smooth  80  valley  floor.  m contour i n Figure  Instead  they  2.6. We b e l i e v e  contours result  radiation  through the i n t e r n a l  shallow  ice  moraine.  The s t r u c t u r e  medial  depths  moraine moraine  medial  moraine.  overridden 1960,  the o c c a s i o n a l layer.  coincides  layer  also  penetration  the  major  ice  originated  of the  the  caused  surface  formation  the  from  the  the  medial of  the  f o r m a t i o n o f an  which t e r m i n a t e s i n t h e v i c i n i t y  Possibly  i c e which  with  have  and t h a t t h e  S e c o n d l y , t h e edge o f  which h a s c a u s e d  could  internal  from  the  that the r i s e s  are too steep f o r a reasonable v a l l e y c o n f i g u r a t i o n irregular  cause  northern  of  the  arm  has  at the southern headwall  (Sharp,  p. 13).  2.4 CONCLUDING REMARKS TO AIRBORNE SURVEYS Our  field  t e s t s demonstrate  that  airborne  can be used t o measure t h e i c e t h i c k n e s s o f sized  cold  valley  glaciers.  The compact  i n s t r u m e n t s makes them e a s i l y aircraft. c a n be  encountered  guickly  of our sounder.  ,. l y i n g  i n , the  Territory,  we sounded  far  ideal  from  and  or d i r t y  Several  northwest  and  ice.  improvements  though  c o l . of  sounders i s t h e i r  the  The  airborne  Narod,  and  medium-  smallest  i c e thickness  efficiently.  D u r i n g an  sounders  o f t h e a n t e n n a and  d e p l o y a b l e from e v e n  430 m o f i c e . under  (Clarke  drawback o f UHF .echo temperate  size  was 200 m on H a z a r d G l a c i e r ,  depth.limit glacier  small  Using a s m a l l h e l i c o p t e r , complete  collected  UHF echo  deepest  data ice  t h i s i s not the survey  of  l i t . Logan,  .conditions  the Yukon  that  were  unpublished).  The  major  inability  penetrate  to  . • to  the  sounder  are  now  being  25  undertaken: these include single  rack-mounted  increased addition  the o r g a n i z a t i o n  package  pre-amplification of a graphic  magnetic  recorder  recording  navigation  display  for  for for  easier  improved  f o r monitoring  digital  aids.  of the radar  or  airborne system and  analogue  into  a  deployment, performance,  field data,  replay, and  a  direct  26  CHAPTER 3:  PHYSICAL PROPERTIES OF  3.1  EXPERIMENTAL  The  experiments  Hazard  Glacier  gather  for  performed camp  with  data  the  (drill  of p o l a r i z a t i o n  statistical  discussed  DESCRIPTION  field  measure e l l i p s e s  GLACIERS  on  site  of  been  reflection  labelled  The  execution  sounder  #1)  at  our  were d e s i g n e d t o  reflected  h e r e a r e t h e p r o d u c t s of two  convenience  UBC  power,  strengths.  experiments  e x p e r i m e n t TX.O  and  to  The  data  which  have  and  experiment  TX.9. physical  rotation  of a r e c e i v e r  transmitter  antenna  of the t r a n s m i t t e r the  flow  axis  was  the  antenna left  antenna  of  of  the  about  involved  the v e r t i c a l  axis,  stationary.  was  aligned  glacier.  approximately p a r a l l e l  F o r TX.9  to  the E-vector of the  a p p r o x i m a t e l y p e r p e n d i c u l a r t o the f l o w a x i s of t h e  angle  to  the  high-gain  corner  reflector  antennae  (App.  f o r t h e s e experiments. Because o f t h e i r s m a l l s i z e to  mount  approximately For  60  the cm  antennae  records on  of by  on  we r e c o r d e d 36  the r e c e i v e r a n t e n n a photographing  Polaroid  rotating  platforms,  1.5)  were  we  were  levelled  above t h e i c e s u r f a c e .  each experiment  increments  display  TX.O  ( F i g . 3.1).  Two  72  right  E-vector  orientation,  able  a  the  while a  was  used  at  F o r TX.O  the  transmitter  glacier  aligned  experiments  film.  an  echograms, t a k e n a t  azimuth. A-scope  We  made a t o t a l  (X-Y)  10<> of  oscilloscope  27  We  then  digitizer. The  digitized  these  This d i g i t i z e r  digital  records  has a p r e c i s i o n  were  o f 0.001"  numerically  increments,  and c o r r e c t e d f o r  digitizer.  A  final  r e c o r d s on a " G r a d i c o n "  time  trace  base  (0.025  interpolated  rotation  on  alignment  mm).  t o 10 n s  the. flatbed  c o r r e c t i o n brought  edges o f the t r a n s m i t t e d p u l s e s i n t o  flatbed  the l e a d i n g  (Figs.  3.2  and  3.3) .  3.2  DATA  The  intent  stationary then  ANALYSIS o f t h e two  EM f i e l d  with  experiments  was t o e s t a b l i s h  the s t a t i o n a r y  a quasi-  t r a n s m i t t e r a n t e n n a , and  t o u s e t h e r e c e i v e r a n t e n n a a s an a n a l y s e r o f t h e r e f l e c t e d  field. expect  I f t h e r e t u r n i n g power were l i n e a r l y to detect a c o s  2  variation  two-fold  symmetry  we s h o u l d  expect  returned  power v s . a z i m u t h .  result  of  of the receiver  always t o  have  a  power  evidence  with  we  should  azimuth.  The  antenna p a t t e r n i m p l i e s t h a t two-fold  Nonpolarized  i n t h e measurement o f a c i r c u l a r  d a t a show l i t t l e  polarized  symmetry  r e t u r n i n g power  in  should  power d i s t r i b u t i o n .  f o r any o f t h e s e  effects.  the  Our  28  3.2.1  EBBOES IN POWEB MEA SUREMENTS  PROCESSING  The  ERRORS  photographic/digitizing  which c o u l d  the  trace, the  Together  case  an o p t i m a l l y  The errors.  less  width  valid  A precision or  many  than  photographic  (brightness)  of  the  along  oscilloscope  timing/power e r r o r s  points  sharp t r a c e  along the  since  trace.  In  had a w i d t h c o r r e s p o n d i n g t o  process can a l s o  contribute  i n o u r c a s e o f 0.001"  0.04 dB,  and  i s  s o u r c e . However u s e r i m p r e c i s i o n errors  recording  100 ns o r 1.5 dB.  digitizing  2.5 n s  the  image d e n s i t y  with the f i n i t e  must v i s u a l l y s e l e c t  approximately  to  speeds  t h i s can r e s u l t i n substantial  user  our  writing  cannot d e l i v e r uniform  trace.  errors  available.  t o cathode r a y tube  process  introduces  have been a v o i d e d h a d a more s o p h i s t i c a t e d  medium been e a s i l y Due  procedure  times l a r g e r .  Time b a s e c o r r e c t i o n  values  timing/power  (0.025 mm)  corresponds  hence n o t a s i g n i f i c a n t e r r o r and  fatigue  We k e p t s e s s i o n s  1 hour t o minimize t h i s  to  could  introduce  at the d i g i t i z e r to  problem. were t a k e n f r o m  O v e r l e a f : F i g u r e 3.1. S c h e m a t i c o f t h e p l a n r o t a t i o n experiments.  points  sampled  views of the antenna  Second o v e r l e a f : F i g u r e 3.2 t h e 36 r e c o r d s f o r e x p e r i m e n t TX.O. The numbers t o t h e l e f t o f e a c h record , indicate the r e c e i v e r azimuth i n degrees. Third  overleaf:  Figure  3.3. The 36 r e c o r d s o f e x p e r i m e n t TX.9.  29  FIG. 3.1 ROTATION  SCHEMATIC  OF  ANTENNA  EXPERIMENTS, PLAN  VIEW  FIG. 3.2  CORRECTED EXPERIMENT  RECORDS "TX.O"  OF  32  along  the l e a d i n g  only  sharply  edge o f t h e o s c i l l o s c o p e t r a c e ;  visible  edges  because o f v a r i a t i o n s i n the power,  this  timing  a l l  strength  c o r r e c t i o n i s not l i k e l y  accuracy to better  measurement e r r o r s Finally, considered  on  of  the r e c o r d s .  However  of  the  arrival  direct  t o have i m p r o v e d  the  t h a n 20 n s , n o r has i t a f f e c t e d  within  after  t h e s e were t h e  gross random  the t r a c e s .  correction,  t o be a s i g n i f i c a n t  trace  error  rotation  was  not  source*  SYSTEM INDUCED EBBOBS  Three being  additional  an i d e a l  antenna  half-space,  position.  interaction changes  in  in  and the  Two  e a c h c a u s e d by t h e g l a c i e r n o t  result i n received  of  of the antenna  these with  power v a r y i n g  effects,  materials  r e s u l t i n mismatches  involving  with  and  gain  variations  in  pattern, the  caused  ice/air  by  surface,  refraction  vary  significantly  with  others,  1972). I c e / a i r s u r f a c e  effect.  W i t h a 36 cm  could  influence  elliptical  beam  that  receiver  the  small  are  pattern. feed  Variations at  random  r e d i s t r i b u t e the  received  power. I t i s w e l l known t h a t r o u g h n e s s c a n c a u s e b e d r o c k to  the  t h e . antenna  f l u c t u a t i o n s i n power f e d t o t h e r e c e i v e r . antenna  with  i n i t s near f i e l d ,  t h e a n t e n n a ' s e f f e c t i v e impedance  Impedance c h a n g e s line  effects,  antenna  movements  roughness could  cause  echoes  (Nye, a  similar  w a v e l e n g t h , r o u g h n e s s on t h e s c a l e o f 36 the  antenna  (approximately antenna  pattern.  18° x 4 4 °  Finally, semi-axes)  and  having  cm an  guarantees  " s e e s " d i f f e r e n t s c a t t e r e r s as t h e  33  a n t e n n a i s r o t a t e d , i n t r o d u c i n g more v a r i a t i o n  in  the  received  power. Our of  data  total  received  follows. vs.  time  0.5  us  then  By  calculated us,  function  we  us  the average 1/R  flatten  o f azimuth  We  2  the  over  t h a t the  record to r e c o r d ,  these t h e 36  power  o f f roughly  1/R  as  variations records of  returning  power  between  5 dB/100 m.  We  power i n e a c h r e c o r d , between 0.5  us  - 5 dB/100 m  plot  2  curve  r e c o r d s . The  on a l i n e a r  -  as  as  a  r e s u l t s are  ( F i g . 3.5)  and  weighting  plotted  as  a  plot  log  a  3.6). The  a l g o r i t h m d e s c r i b e d above i s t o some e x t e n t  However, t h e r e a r e f e a t u r e s i n F i g s . certainly  occur  difference  between t h e  experiment.  In  with  both  power.  At  several  any  s t r o n g e s t and  apparent  locations  between a d j a c e n t a n t e n n a If  these  3.5  estimator.  experiments  Another f e a t u r e i s the  occur  from  estimated  average  noted  falls  u s i n g the  to  function (Fig.  the  ( F i g . 3.4A) 1.5  large variations,  power.  taking  and  1.5  and  exhibit  and One  is  which the  would  very l a r g e  weakest r e t u r n s w i t h i n  the  difference  randomness jumps  3.6  arbitrary.  of  one  e x c e e d s 25 the  dB.  estimated  i n power e x c e e d i n g  ±10  dB  positions.  v a r i a t i o n s have been c a u s e d  by e f f e c t s  other  than  Overleaf: F i g u r e 3.4. A v e r a g e s o f power v s . t i m e . T h e s e r e c o r d s are the averages of the 36 individual records of each experiment. In 3.4A the o r i g i n a l d a t a have b e e n a v e r a g e d . In 3.4B each i n d i v i d u a l r e c o r d has been s c a l e d up or down to an average level by s u b t r a c t i n g t h e r e l a t i v e power f i g u r e p l o t t e d i n F i g 3.6. We have c a l l e d t h i s p r o c e s s " a z i m u t h a l s m o o t h i n g " . 1/R  2  S u p e r i m p o s e d on e a c h r e c o r d i s a c u r v e which - 5 dB/100 m f a l l - o f f o f power w i t h d e p t h .  represents  a  7C  RELATIVE  POWER  (10dB/DIV)  RELATIVE  POWER  (10 dB/DIV)  RELATIVE  POWER  RELATIVE  POWER  (5dB/DIV.)  37  the  random  surface  we s h o u l d  azimuthal Fourier there  interaction expect  functions  spectra is  no  thus that  of  the g l a c i a l  these  preclude detection  The for  power.  two-fold  symmetry  Examination  of t h e r e l a t i v e  of p o l a r i z a t i o n should harmonics  of  in  the  power  the  discrete  reveals  that  properties  from  estimated  by  a z i m u t h a l power f u n c t i o n s .  The  a d d i t i o n a l random  measurement  also  be  variations  of e l l i p t i c i t y  in  our  data  of p o l a r i z a t i o n , and  of b i r e f r i n g e n c e .  DIELECTRIC ATTENUATION  72 r e c o r d s  estimating  averages  a  and t h e i c e / a i r  i c e mass.  even  3.2.2  see  antenna  v a r i a t i o n s a r e n o t c a u s e d by b u l k  magnitudes o f these  the  of  ( F i g . 3.7)  Ellipticity  thus  to  the  t e n d e n c y f o r t h e even h a r m o n i c t e r m s t o d o m i n a t e ,  and  extracting  between  of  of experiments  the d i e l e c t r i c the  records  TX.O  and TX.9 p r o v i d e  losses i n  have  been  the  glacier  plotted  a  basis  ice.  The  i n F i g 3.4A.  e s t i m a t e t h e e f f e c t o f t h e l a r g e random v a r i a t i o n s d i s c u s s e d Sec.  3.2.1,  scaled  have  each r e c o r d  was  done  Fig.  3.6  power  we  by from  figure  also  subtracting  from  always y i e l d  ±1 dB. We  described  a relative  and  adding  changes  the  the  having This  have  average  In t h i s  i n the previous  we  in  power f i g u r e p l o t t e d i n  power f i g u r e e q u a l  p r o c e d u r e , which  after  variations.  F i g . 3.6 t o a l l t h e r e c o r d s .  -  smoothing,  record,  records  large  the r e l a t i v e  i t s respective  power f i g u r e . T h i s  the  to correct f o r these  power e s t i m a t i n g a l g o r i t h m would  averaged  way t h e  subsection  t o the average  called  azimuthal  peak power r e f l e c t e d a t t h e b e d r o c k  can c o n c l u d e from t h i s  small  To  deviation that  the  by  large  °(1112) * (843)  FIG. 3.7 DISCRETE  HARMONIC NUMBER FOURIER SPECTRA OF AZIMUTHAL  POWER  39  record  to  record  t o measure an  v a r i a t i o n s do  3.4,  requires  commonly u s e d  -81 -14 -20 + 31 -14 -98  b e d r o c k echo s t r e n g t h , To  we  length  c o r r e c t i o n s , of  total  dielectric  dielectric  or  us  i s -20  dB  f o r the (Davis,  corresponding 158  losses ftanS  m. be  to  T h e s e two 14  = 0.26.  1  dB,  dB dB dB dB dBdB  determined  dielectric  assume a v a l u e  value  1.85  compute t h e  is  dB/100m  Computation  Geometric l o s s e s at 158m System l o s s e s Bedrock r e f l e c t i v i t y Two-way a n t e n n a g a i n Dielectric losses  delay  4.5  Loss  ability  power.  + 66 dBm -32 •dBm 98 dB  dBm.  that  Dielectric  a f f e c t our  Transmitted power R e c e i v e d power  measured  i s -32  adversely  average bedrock r e f l e c t i o n  T a b l e 3.1.  The  not  from  Fig.  l o s s e s f r o m one  datum  bedrock r e f l e c t i v i t y . unpublished).  an  The  echo  i c e depth, with  cable  figures reguire yielding  table  A  3.1  loss  that  the  rates  of  summarizes  the  loss calculation.  *We must be aware t h a t t h e b e d r o c k r e f l e c t i v i t y v a l u e of -20 dB represents a s i m p l i f i c a t i o n o f the combined d i e l e c t r i c c o n t r a s t and s u r f a c e r o u g h n e s s e f f e c t s , and was s e l e c t e d t o account for radio echo sounder behaviour' at VH f r e q u e n c i e s . To use t h i s f i g u r e h e r e we must assume that this simple description of b e d r o c k b e h a v i o u r c a n be e x t e n d e d , u n c h a n g e d , t o UH frequencies. This is not n e c e s s a r i l y t h e c a s e s i n c e f e a t u r e s s u c h as w a t e r f i l m s may have s u b s t a n t i a l e f f e c t s a t the hiqher frequencies. Nonetheless since we have no o t h e r e s t i m a t e we s h a l l use t h i s figure.  40  The  mean  experiment  ice  site  temperature  is  known  p r i v a t e communication). very  well  with  of  Hazard  Glacier  at  ( F i g . 3.8) t o be a b o u t -5°C  The v a l u e  o f f t a n 8 = 0.26  measurements o f W e s t p h a l  (Evans,  the  (Clarke,  a t -5°C a g r e e s  1965).  3.2.3 SCATTERED POWER DENSITY VS. DEPTH Given  from  dielectric Fig.  losses  3.4 t h a t  coefficient, 5(1))  the  previous  are  about  subsection  that  9 dB/100 m, we may site  C,  (unpublished,  increases  defined  with  by D a v i s  two-way  now i n f e r  a t Hazard G l a c i e r d r i l l as  #1  the  the  from  scattering p. 64, eq"n  depth.  (3.1)  where Pg i s t h e s c a t t e r e d incident  power  density.  9 dB/100 m r e q u i r e s of  radius  R,  power p e r u n i t volume and  that  fall  A constant received  off  with  u n p u b l i s h e d , p . 66, eq'n 5 ( 3 ) ) . is  best  that  fitted  the  scattering  implication scatterers increases  by a 5dB/100m  of this  with  depth.  1/R  2  a  - 9 dB/100m  the s i z e  with and/or  shell (Davis, power  conclude  depth. density  water c a v i t i e s ,  the  losses of  from  ( F i q . 3.9) we  increases  debris,  is  the a c t u a l s c a t t e r e d  l o s s curve,  coefficient  rock  as  Since  r e s u l t i s that  (presumably  C and d i e l e c t r i c  power s c a t t e r e d R  P  The of  conduits)  FIG. 3.8 THERMAL  REGIME  OF HAZARD GLACIER DRILL  • 76T1 x76T2 o 76T8  !  8  •  •  -6  I  I  i-Z  -U  TEMPERATURE  1  1  -2 (°C)  I  0  SITE  1  > Q \ CD  TX.O  O  AVERAGE  AFTER  PRESCALING  or LU  o Q_ UJ >  LU  or  0  5dB/100m  FALLOFF  9dB/100m  FALLOFF  0.5  1.0 DELAY  FIG. 3.9  LOSS  1.5 TIME (psec)  COMPARISON AND  2.0  OF  DIELECTRIC  SCATTERED  POWER  43  3.3  DETECTION OF LARGE CONDUIT  SCATTERERS  A f u r t h e r e x a m i n a t i o n o f F i g . 3.4 r e v e a l s t h a t delay  1.5 us  of  the  average record  peak 5 dB above t h e l o c a l in  the  average  possibility identify  record  o f using  represent  the  of  high  large conduit  discusses  time  o f TX.O  average.  TX.9.  or  This  section  examines  possibility  "linear"  scatterers,  t h a t data  a t time delay  signature  FOR  patterns, i . e .  scatterer,  present  rotation  experiment,  scattering  o b j e c t . By m o d e l l i n g  ribbon  scatterer,  strong  the  r e s o l u t i o n UHF r a d i o e c h o s o u n d i n g t o  THEORETICAL PATTERNS  a linear  flat  exhibits a  time  T h i s peak i s n o t e v i d e n t  and  further,  1.5 us m i g h t  CONDUIT SCATTERERS  We h a v e t a k e n t h e a p p r o a c h t h a t l i n e a r  by  a  such a s c a t t e r e r .  3.3.1  generate  at  (Appendix  t o the t o t a l  may  the p a t t e r n o f data  in  the  somehow  be  range  transmitted  of  as  objects produced  an  identified  the s c a t t e r e r  3) t h e r a t i o  + ~7F I J ( P / 8 )  scattering  a  antenna with  the  horizontal  o f power r e c e i v e d  from t h e  power max be e s t i m a t e d  by  exp(-i^-P)|  (3.2,  c f . A3.59)  44  where  ( s e e F i g - A3. 1) W i s t h e w i d t h o f t h e s c a t t e r e r , Xi  scatterer of  depth, G i s the antenna g a i n  nearest  A3.37,  is  respective relative  vertical may  antenna azimuths  pattern  dependent.  of  transmit  approximation  the  several  and J, d e f i n e d a  and  T  and  a  R  receive  angle by  eq'n  are  the  antennae  normal. is  valid  i f  angle of i n c i d e n c e r e q u i r e d  be  f u n c t i o n , /3 i s t h e  (angle o f i n c i d e n c e ) ,  t o the s c a t t e r e r  The  W  approach  i s the  wavelengths.  Wsin/3<<1.  by  For the  our h i g h - g a i n  near  antennae,  I n o u r c a s e , w i d t h s up t o 1 m  may  be r e a s o n a b l y m o d e l l e d . Equation evaluation dependent  3.2  comprises  of the i n t e g r a l only  on  the  two  parts.  The  over a removable gain  of  first  term  singularity,  the  antennae  i s the and  toward  is the  F i r s t and s e c o n d o v e r l e a v e s : F i g u r e 3. 10. Theoretical antenna rotation patterns f o r the U.B.C. h i g h - g a i n corner reflector a n t e n n a e . The two r o s e t t e s model r e s p e c t i v e l y experiments TX.O and TX.9. I n e a c h r o s e t t e t h e r e a r e two c u r v e s . The o u t e r d a s h e d curve plots the r e l a t i v e power c a l c u l a t e d u s i n g t h e n u m e r i c a l scheme d e f i n e d i n A p p e n d i x 3. These v a l u e s have b e e n normalized to the maximum v a l u e f o r t h e two model e x p e r i m e n t s . The i n n e r s h a d e d c u r v e , a l w a y s two p e t a l s , i s t h e p r o d u c t o f t h e v a l u e of the f i r s t c u r v e with e i t h e r c o s # o r s i n ^ . The s e c o n d c u r v e s show t h e e x p e c t e d p a t t e r n s i f t h e backscattered radiation has t h e i d e n t i c a l p o l a r i z a t i o n t o t h e i n c i d e n t p o l a r i z a t i o n . Here we have assumed t h a t no d e p o l a r i z a t i o n o r p o l a r i z a t i o n r o t a t i o n h a s occurred. 2  Superimposed on e a c h r o s e t t e of the scatterer position. The scatterer, oriented at angle a a n g l e ,/3 o f f o f t h e v e r t i c a l . F u l l 450 o f f v e r t i c a l . in  2  i s a schematic r e p r e s e n t a t i o n heavy line represents the (see F i g . A 3 . 1 ) , d i s p l a c e d by scale displacement represents  The l a r g e dynamic r a n g e a t P =20° i s due the antenna E-plane at about 2 0 ° .  Third and fourth overleaves: Figure r o t a t i o n p a t t e r n s f o r d i p o l e antennae. 3. 1 0 .  to a  strong  null  3.11. T h e o r e t i c a l antenna See d e s c r i p t i o n of F i g .  45  270  FIG. 3.10  SAMPLE  PATTERNS  THEORETICAL FOR  CORNER  A N T E N N A ROTATION REFLECTOR  ANTENNAE  46  270  270  180  \  2  7  0  r  L  a = 45  TX.O  0  $  A  olTX.9  0 XI  X  0  90  270  180  FIG. 3.10  CONT.  FIG. 3.11 S A M P L E PATTERNS  THEORETICAL FOR  DIPOLE  ANTENNA ANTENNAE  ROTATION  48  FIG. 3.11  CONT.  49  scatterer's the  nearest  residual  the  gain  point  G(/8,ct). T,K  difference  The s e c o n d  dependent i n t e g r a l .  evaluated  several  3.11).  contribution larger extends  than 9  and s i n g l e In  3  power p a t t e r n  half-wave dipole  a l l cases  Appendix  both our h i g h - g a i n  we  have  that  from  corner  antennae  found  we  (Figs. the pole  t o t h e i n t e g r a l i s a t l e a s t two o r d e r s o f m a g n i t u d e the r e s i d u a l contribution,  t o well  component, entire  positions, modelling  antennae,  and  in  t h e c o n t i n u o u s wave r e t u r n i n g  scatterer  reflector 3.10  evaluates  between t h e r e m o v a b l e s i n g u l a r i t y and  U s i n g t h e n u m e r i c a l scheme e s t a b l i s h e d have  term  and  beyond  e v e n when t h e i n t e g r a t i o n  45<>. We c a n t h e n  consider  the  pole  term  neglect  the  residual  alone t o represent t h e  integral  ±  JL  L-p^J  =  Since the only  8^X7* • 6 ( ^ , a ) G . O , a ) C 0 S ^ [ T  a.  and (B dependence now  G ( p, dj ) G ( yS , a ) , R  indistinguishable  the  from t h a t  shape of a point  occurs  of  o r i g i n . , Hence, t h e s h a p e o f t h e p a t t e r n  to  identify line  scatterers.  3.3 may  be  rewritten  the  in  alone  ( 3  the  .  3 )  factor  pattern  scatterer located  L  Eguation  J  H  at  is the  c a n n o t be used  50  indicating reflector  that backscattered backscatters  power f a l l  power  b a c k s c a t t e r s power a s  B~*.  scatterer  identified  location. of  the  cannot  be  A positive scatterer  backscattered  as  As d e t e r m i n e d by  identification from  power t o t h e  E  several fi-  data  off - 2  .  as A  B~ .  A  3  point  plane  scatterer  above, a  large  linear  collected  from a  single  would r e q u i r e radar  sites  the and  locating  fitting  the  curve.  3  F i r s t and s e c o n d o v e r l e a v e s : F i g u r e 3.12. TX.O a n t e n n a rotation data selected at various d e l a y t i m e s . The f i r s t e l e v e n p l o t s h a v e been s e l e c t e d a t 100 ns i n t e r v a l s , i n t h e r a n g e 0.7 us to 1.7 u s . The last nine p l o t s have been selected at 20 ns i n t e r v a l s i n a range c o v e r i n g t h e l e a d i n g edge. of the bedrock echo a t 1-8 u s . Each rosette has been n o r m a l i z e d t o t h e maximum v a l u e o f t h e d a t a used i n t h e r o s e t t e and p l o t t e d on a l i n e a r scale. To the right of e a c h r o s e t t e a bar g r a p h d i s p l a y s r e l e v a n t power data. The bar graph i s logarithmic with the full scale representing 80 dB. The t o p o f t h e d a r k band i n t h e l e f t c o l u m n i n d i c a t e s t h e l e v e l o f t h e 1/E - 5dB/100m estimator described i n S e c t i o n 3.2. The t o p and b o t t o m o f t h e d a r k band i n t h e r i g h t column mark the maximum and minimum power p l o t t e d i n the c o r r e s p o n d i n g r o s e t t e . As t h e d e l a y t i m e p a s s e s i n t o t h e b e d r o c k echo t h e power l e v e l can c l e a r l y be s e e n t o r i s e w e l l a b o v e the s c a t t e r e d power e s t i m a t o r . 2  Third data.  and f o u r t h o v e r l e a v e s : S i m i l a r t o F i g . 3.12.  F i g u r e 3.13.  TX.9  antenna  rotation  F i f t h and s i x t h o v e r l e a v e s : F i g u r e 3.14. TX.O antenna rotation data after azimuthal smoothing. The r a t i o of t h e maximum t o minimum power ( t h e l e n g t h o f t h e d a r k band i n the right column of the bar graphs) are generally smaller than those of the unsmoothed d a t a s u g g e s t i n g t h a t a z i m u t h a l s m o o t h i n g has tended to remove l a r g e - s c a l e , e x t e r n a l l y c a u s e d e f f e c t s . The s p i k e y a p p e a r a n c e a t t h e d e l a y t i m e s 1.80 us t o 1.84 us c a n r e s u l t f r o m two c a u s e s - a s e v e r e l y d i f f e r e n t b e d r o c k s c a t t e r i n g r e g i m e , o r , more l i k e l y , t i m i n g e r r o r s . Seventh and eighth antenna r o t a t i o n data  overleaves: Figure 3.15. Selected TX.9 a f t e r a z i m u t h a l s m o o t h i n g . See F i g . 3.14.  T=0.800 uSEC  FIG. 3.12  SAMPLED  ANTENNA  FROM  "TX.O"  ROTATION  DATA  FIG. 3 12  CONT.  53 T=0.700 uSEC  0  270  T=0.800  270/  \  MSEC  ]90  180 0  T=0.900 jiSEC  270/  j 1  90  0  270/  ^^~~>  180  0  270/  1  90  0  1 90  0  I 1 3^  180  190  180  T= 1.300 uSEC  270/  T=1.100 uSEC  270/  180  T= 1.200 uSEC  ' C  T= 1.000 USEC  I  0|T=1.400 uSEC  90  180  0|T=1.500nSEC  0  T= 1.600 uSEC  270/  1  90  180  FIG.  3.13 S A M P L E D  ANTENNA  FROM  "TX.9"  ROTATION  DATA  T= 1.760 uSEC  FIG. 3.13  CONT.  T=0.800 uSEC  FIG.  3.U FROM  SAMPLED "TX.O",  ANTENNA AFTER  ROTATION  DATA  A Z I M U T H A L SMOOTHING  56  180  FIG. 3 . U  CONT.  57 0  T=0.700uSEC  >  270 /  1  0  90  270 /  \  \  180  0  (  I 90  1 90  180  T=0.900uSEC  270/  T=0.800 uSEC  0  T= 1.000 uSEC  270/  1  —<-m.  180  J  o  0  90  270/  V  T= 1.300 uSEC  0  J  0  270/  C  180  FROM  180  ^  1  0|T=1.700nSEC  9 0  180  FIG. 3.15 S A M P L E D  ANTENNA  "TX.9", AFTER  1 90  r  T=1.600MSEC  <  90  T= 1.400 uSEC  270  180  0 T= 1-500 uSEC  1  180  5V  270/  no I  /  180  0  T= 1.100 uSEC  ROTATION  AZIMUTHAL  DATA  SMOOTHING  FIG. 3.15  CONT.  59  3.3.2  COMPARISONS WITH THE  Figs. t h e two vs.  3.12  The  f o r the  smoothing  selected  data  patterns.  which  patterns  corner r e f l e c t o r requires  that  polarization  we  by  the  us  are  invoke  and  the  o f o b s e r v i n g any time  field  tests  two-fold  and  vs.  time  displays  data.  patterns  of  the  symmetrical well  with  u s i n g an least  petal any  idealized  match  also  rotates  the  theoretically  receives  its  regarding symmetry,  the  very  the  low  appearance  fortuitous.  d i s c u s s i o n s have d e m o n s t r a t e d  or  of  of  UHF  other  collected  to provide the  echo  glaciers.  by  sounders  require  r e p r o d u c t i o n of  photographing  accuracy  the for  Measurements  parameters  a c c u r a t e r e c o r d i n g and  have f a i l e d  and  CHAPTER 3  properties  Records  3.14  us i s most l i k e l y  physical  f o r the  after  which  data  determining  capability  provide  90°.  a s s o c i a t e d w i t h t h e use  birefringence  the  mechanism  two-fold  1.50  power  (Figs.  compare  even  difficulties  attenuation,  only  have g e n e r a t e d  CONCLUDING REMARKS TO  These  the  not  at  of  3.15).  s i n c e TX.O TX.9  received  smoothed d a t a  do  some  consider  symmetry a t d e l a y  3.4  and  from  t h a t we  plotting  t w o - f o l d symmetry, even  resemble  a b o u t 90°  we  probability  3.14  still  of r o s e t t e p l o t s  a parameter. These p l o t s  model. To a c h i e v e  power a t 0<>  When  of  1.50  However, t h e y  theoretical  greatest  (Figs.  time  as  expected  rosettes plotted  at delay  are s e l e c t i o n s  experiments,  with d e l a y time  evidence  azimuthal  3.15)  3.15  antenna r o t a t i o n  azimuth,  little  through  FIELD EXPERIMENTS  of a  power  A-scope  required for  these  60  e x p e r i m e n t s . More i m p o r t a n t , random surface, appear  perhaps d e n s i t y  plane  be  At  840  MHz  surface, with  the  thus  sufficient  u s e d . Our  attenuation  sufficient  redundancy  mainly  The  last  drawback  approach t o thousands  a  a statistical  only  that  i t  may the  another  measurement  on  be-  the  a s i n g l e record  may  collected  order the  of  reguire  Glacier require surveys.  an  surface  accurate,  In  addition we  system  digital,  cassette  logging  accurate  records  than  our  are  concurrently  do  a field  literally experiment.  of  labour  will support  to  to  process  medium  measurements  as  do  airborne  modifications developing  e x p e c t i t to  photographs,  format. I t  power-hungry o s c i l l o s c o p e and  We  serious  prohibitive.  scheduled  system.  with  statistical  that  minutes  serviceable recording  airborne  computer c o m p a t i b l e  A  experiments f o r i c e p r o p e r t i e s  to  the  reliable,  amount o f t i m e r e q u i r e d  l a r g e number o f p h o t o g r a p h s would be  may  reflectivity.  technigue.  ten  a  collect  made  potentially  during  the  as  b a s e d on  considered  bedrock  of  approach  measurement be  ice,  modelled  b a s e d e x p e r i m e n t must  photographic recording  records  i t requires  c a n n o t be  our  suggest  ice/air  near~field  is  knowledge of  parameter of  digitize  our  the  near-surface  o f f t a n S = 0.26,  comments  of the  surface  at  estimate  records,  by  surface  redundancy t h a t  72  limited  glacier any  average of  Since  v a r i a t i o n s w i t h i n the  t o cause l a r g e s c a l e v a r i a t i o n s i n the  antenna.  data  roughness  also  and  a  i n an  our  portable,  provide  eliminate  hardware.  to  more  immediately a  heavy,  61  CHAPTER  4.  CONCLDDING  REMARKS  AND  RECOMMENDATIONS FOR  FUTURE  EXPERIMENTS The view  work r e p o r t e d  towards r a d i o  with  many s m a l l  including  airborne ice  The are  echo s o u n d i n g .  and  alpine  should  840  be  MHz  advantages  the  to t h i s  aircraft  surveys are  can  interference.  Also,  problems a s s o c i a t e d  since  an  UHF  small  aircraft Our  radar  Hazard G l a c i e r  840  MHz  these  system  indicating  confirm  to  small  a  large  be  introduced  UHF  gain  to  as  at t h e  ice/air  a l l of  and these  sounder. antennae  implies  that  where  light  antennae  aircraft  minimize  would  Archipelago from  ease  ice  one  caps  of-  the  areas.  based experiments c a r r i e d out with  f t a n 8 = 0.26  u s e f u l r a d i o echo  changes  a  extreme  in  the  perfect  ice/air plane.  surface.  to  overcome t h e  on  -5°C,  sounding  band.  sensitivity  of  position,  surface Any  may  not  successful  stress  internal structure  simply  at  antenna  m o n i t o r s u c h " e f f e c t s as  redundancy  ice  developing  This  operated  frequencies  modelled  several  valleys  light  be  i n the  these  as  m  s e v e r a l . UHF  small  high  bedrock roughness or  data  an  aircraft.  that  scale  700  well  have shown by  t e s t s a l s o demonstrate the  experiments performed anisotropy,  depth,  than  i n mapping t h e  surface  included  that at  necessarily  less  of  survey could  from  the  However  of  which r o u t i n e l y s e r v i c e t h e s e  results  must be  dotted  in  the - use  logistic  Canadian A r c t i c i s  approach are  where  Canadian  The  range of  operate  n e c e s s a r y and  particularly  echo sounder t h a t  r e a d i l y d e p l o y a b l e from l i g h t  airborne  our  We  radio  within  a  g l a c i e r s , as  A r c t i c Archipelago.  t e s t i n g an  fields  taken  i c e masses l i k e l y  valley  caps i n the  h e r e has  will  induced require  random e f f e c t s  62  A common t h r e a d r u n n i n g t h r o u g h the  a l l of t h i s  work  has  been  f a i l u r e o f our p h o t o g r a p h i c r e c o r d i n g procedures t o p r o v i d e  reliable future  and r e c o v e r a b l e d a t a . We c a n experiments  medium, p r e f e r a b l y continuous scope),  be p e r f o r m e d  for  recommend  with  airborne  capabilities  surveys  recorders  We a r e , i n f a c t , as  two  c h a n n e l FM t r a n s p o r t transport.  presently  separate and  developing  systems.  the  second  a  both t o Z-  (analogous t o  both  The f i r s t on  for  (analogous  and s p o t r e c o r d i n g f o r s u r f a c e e x p e r i m e n t s  A-scope).  that  w i t h some a l t e r n a t i v e r e c o r d i n g  magnetic tape,  recording  strongly  types  i s based  digital  of  on a 4  cassette  63  LITERATURE CITED B a i l e y , J . T., and o t h e r s . 1964. R a d i o - e c h o s o u n d i n g o f p o l a r i c e s h e e t s , by J . T. B a i l e y , S. Evans and G- de Q. R o b i n . N a t u r e , V o l . 204, No. 4957, p. 420-21. Beckmann, P., and S p i z z i c h i n o , A. 1 9 6 3 . The s c a t t e r i n g of e l e c t r o m a g n e t i c waves from rough s u r f a c e s . . 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U n p u b l i s h e d . , The p r o b l e m o f d e p t h s o u n d i n g t e m p e r a t e g l a c i e r s . l_M.Sc. t h e s i s , U n i v e r s i t y o f C a m b r i d g e , 1973i J  64  D a v i s , J . L., and o t h e r s . 1973. B a d i o e c h o s o u n d i n g o f a v a l l e y g l a c i e r i n E a s t G r e e n l a n d , b y - J . L. D a v i s , J . S. H a l l i d a y and K. J . M i l l e r . J o u r n a l of G l a e i o l o q y , V o l . , 1 2 , No. 64, p. 87-91. ;  D e l c o . 1971. 28 v o l t D a r l i n g t o n s w i t c h i n g r e g u l a t o r . E l e c t r o n i c s a p p l i c a t i o n n o t e #49, December 1971  Delco  E v a n s , S. 1965. D i e l e c t r i c p r o p e r t i e s o f i c e and snow r e v i e w . J o u r n a l o f G l a e i o l o q y , V o l . 5, No. 42, p. Goodman, B. H. 1975. B a d i o echo s o u n d i n g J o u r n a l o f G l a e i o l o q y , V o l . 14, No.  a 773-92.  on t e m p e r a t e g l a c i e r s . 70, p. 57-70.  Goodman, B. H. and o t h e r s . 1975. B a d i o s o u n d i n g s on T r a p r i d g e G l a c i e r , Yukon T e r r i t o r y , Canada, by B. H. Goodman, G. K. C. C l a r k e , G. T. J a r v i s , S. G. C o l l i n s and B. M e t c a l f e . J o u r n a l o f G l a e i o l o q y , V o l . 14, No. 70, p. 79-84. G r a d s h t e y n , I . S.; and B y z h i k , S e r i e s , and P r o d u c t s . New  I . M. York*  1965. T a b l e s - o f I n t e g r a l s , Academic P r e s s .  Gudmandsen, P, and o t h e r s . 1976. New eguipment f o r r a d i o - e c h o s o u n d i n g , by P. Gudmandsen, E. N i l s s o n , M. P a l l i s g a a r d , N. Skou, and F. S o n d e r g a a r d . E l e c t r o m a g n e t i c I n s t i t u t e , t h e T e c h n i c a l O n i v e r s i t y o f Denmark, Lyngby, D 257, 5 p. [ r e p r i n t e d f r o m the A n t a r c t i c J o u r n a l , X ( 5 ) , 1975, p..2346. a H a r r i s o n , C. fl. 1973. B a d i o e c h o s o u n d i n g o f h o r i z o n t a l l a y e r s i n i c e . J o u r n a l o f G l a e i o l o q y , V o l . 12, No. 66, p. 393-97. Huynen, J . B. 1978. P h e n o m e n o l o g i c a l t h e o r y o f r a d a r t a r g e t s . ( U s l e n g h i , P. L. E. ed.) E l e c t r o m a g n e t i c S c a t t e r i n g . New Y o r k , Academic P r e s s , p.653-712. J a s i k , H. ed. McGraw -  1961. A n t e n n a e n g i n e e r i n g Hill.  handbook. New  York,  J o h a r i , G. P., and J o n e s , S. J . 1975. E f f e c t s due t o d o u b l e r e f r a c t i o n i n e c h o - s o u n d i n g of i c e . G l a c i p i g g y . D i v i s i o n , Dept. o f t h e E n v i r o n m e n t , B e p o r t No. 113-75G, 562 B o o t h S t . , O t t a w a , Canada.  65  L o n g h u r s t , R. S. Longmans. Myers, a . e d . edition.  1957.  G e o m e t r i c a l and  physical Optics.  London,  1 9 7 5 . The r a d i o amateur's handbook, f i f t y - s e c o n d A m e r i c a n fiadio R e l a y L e a g u e , Newington, Conn.  N a p o l e o n i , J . G. P*, and C l a r k e , G.-K. C. d r i l l i n g i n a c o l d g l a c i e r . Canadian S c i e n c e s . V o l . 1 5 , No. 2 , p. 3 1 6 - 2 1 .  1 9 7 8 . Hot water Journal of Earth  N a r o d , B. B. U n p u b l i s h e d . UHF r a d i o echo s o u n d i n g o f g l a c i e r s , l_M.Sc. t h e s i s . U n i v e r s i t y o f B r i t i s h C o l u m b i a , 1 9 7 5 . J Nye,  J . F., and o t h e r s . 1972. P r o p o s a l f o r m e a s u r i n g t h e movement o f a ^ l a r g e i c e s h e e t by o b s e r v i n g r a d i o e c h o e s , J . F . Nye, R. G. Kyte and D. C. T h r e l f a l l . J o u r n a l o f G l a c i o l o g y . V o l . 11, No. 63, p. 319-25.  by  O s w a l d , G. K. A. U n p u b l i s h e d . R a d i o echo s t u d i e s o f p o l a r g l a c i e r b e d s . J.Ph.D. t h e s i s . U n i v e r s i t y o f C a m b r i d g e , 1975.J P a n o f s k y , W. K. H., and- P h i l l i p s , M. 1962. C l a s s i c a l and magnetism. R e a d i n g , Mass., A d d i s o n - W e s l e y .  electricity  R o b i n , G;' de Q. 1975. R a d i o - e c h o s o u n d i n g : g l a c i o i o g i c a l i n t e r p r e t a t i o n s and a p p l i c a t i o n s . J o u r n a l o f - G l a e i o l o q Y , V o l . 15, No. 73, p. 49-64. S h a r p , R. P. 1960. G l a c i e r s . E u g e n e , O r e g o n , Oregon P r e s s .  University  of  S m i t h , B. M. E . , and E v a n s , S. 1972. R a d i o echo s o u n d i n g : a b s o r p t i o n and s c a t t e r i n g by water i n c l u s i o n s and i c e l e n s e s . J o u r n a l o f G l a c i o l g g y , V o l . 11, No. 61, p. 133-46. S o n d e r g a a r d , F., and Skou, N. 1976. R a d i o g l a c i o l o g y s i d e - l o o k i n g r a d a r i m a g i n g and d e p t h s o u n d i n g s o f i c e a t 300 MHz. E l e c t r o m a g n e t i c s I n s t i t u t e , the T e c h n i c a l : u n i v e r s i t y of Denmark, L y n q b y , R 170, 51 p. S t r a t t o n , J . A. Hill.  1941.  E l e c t r o m a g n e t i c Theory. .  New  York, McGraw -  66  Swxthxnbank, C. 1968. B a d i o echo s o u n d i n g o f A n t a r c t i c g l a c i e r s from l i g h t a i r c r a f t . Onion G e o d e s i g u e e t Geojohysigue Internationale. Association Internationale d'Hydrologie S c i e n t i f i g u e . Assemble ' g e n e r a l e de Berne, 25 SeptT-7 O c t . J S 6 7 . I C o m m i s i o n de N e i g e s e t G l a e e s . J B a p p o r t s e t ~ d i s c u s s i o n s , p. 405-14. W a i t e , A.H. 1966. I n t e r n a t i o n a l e x p e r i m e n t s i n g l a c i e r s o u n d i n g , 1963 and 1964. C a n a d i a n J o u r n a l o f E a r t h S c i e n c e s , V o l . 3, No. 6, p. 887-92.  67  APPENDIX J : DETAILS OF  A1.1  RADIO ECHO SOONPES  GENERAL DESCRIPTION AND  This  appendix  section  i s an  various  pieces  of the  system.  which t h e  new  sections  deal  receiver,  the  be  is  notice  into five  sections.  which d e t a i l s how  r a d i o e c h o s o u n d e r and  In  principle  user  need  in  detail  regulating  consulted  of each p a r t  he  this  turn  well  first  to connect to operate  only  section  with  with  the  transmitter,  and  the  four  antenna.  complete  the They  t h a n a b a s i c knowledge o f include  the the  remaining  These s e c t i o n s as  The  The  power s u p p l y more  how  i s the  concerned.  in  when  component i s r e q u i r e d . diagrams  OPERATION  divided  operations  complete  should  THE  the  circuit  as f u n c t i o n a l d e s c r i p t i o n s o f a l l  circuitry. This  appendix i s intended  description  of  the  project,  radio  echo sounder other  s e r v i c e the  an  exact  r a d i o echo sounder as  field  and  t o be  however i t has  been  than the  written  user s e r v i c i n g i s p o s s i b l e .  used d u r i n g so  author w i l l  sounder, the l a t t e r  at  specification  that be  the  1976  a user of  able  to  and  the  operate  l e a s t i n components  where  68  A1.1.1  SYSTEM  ASSEMBLY  POWEB SUPPLY AND  The  power f o r t h e r a d i o  instruments fed  into  insert  In  receives  i s connected  are  connected  are  The c o n n e c t o r  with the  while  five  pins.  connector The any  the  power f r o m for  pin  power  when the  The  which  can  of t h e  connection  connection  (Fig.  provide  will  the regulator.  not  draw  and  is  D of  each  run  off  expansion. A1.1)  be  will  10A a t 22 V t o 28 V, f o r i n s e r i e s or  S i n c e each  f o r connection, care  must  regulator  connector  C  connecting i t to the switching regulator. power  pin  oscilloscope  Pin  i n an a i r c r a f t .  system  while t h e  additional  b a t t e r i e s connected  circuit  h a s i t s own  the  instruments.  r a d i o echo sounder  source  auxiliary  usually  B.  are reserved f o r future  example two a u t o m o t i v e 28 V  receiver  auxiliary  assembled  each  r e f e r e n c e . . I n n o r m a l use t h e  and  available  Pin A of  t o t h e i n p u t power,  on  unregulated  four  t o the output o f t h e s w i t c h i n g r e g u l a t o r .  t o the ground  while  the  a s power o u t p u t s .  the output  A  .Power i s circular  t r a n s m i t t e r a l w a y s draws power from pin  any. a u x i l i a r y  standard  power  a r e used  there  p i n B's a r e a l l c o n n e c t e d  E*s  panel.  incoming  inserts  connector  and  v i a one o f t h e f i v e  the  with female  sounder  by t h e s w i t c h i n g r e g u l a t o r .  regulator  each  connector  echo  on t h e r e g u l a t o r f r o n t  connectors  The  i s distributed the  connectors male  DISTRIBUTION  reversed.  a  power  must  10A, source  be  taken  The p o l a r i t y o f An  incorrect  d e s t r o y t h e high-power s w i t c h i n g t r a n s i s t o r i n When  properly  connected  and  functioning  the  REGULATOR 22-28vDC POWER IN  N Z CM  Trig  N\ CIRCULATOR N TRANSMITTER  FIG.A1.1  RADIO  Ch2  T  RECEIVER  ECHO  SOUNDER  BLOCK  DC POWER trig  OSCILLOSCOPE  DIAGRAM  70  regulator  will  frequency output  either  on  the  Should circuits  power d i o d e  function  V.  over  26  the  whine  The  input  setting and  the  monitor  high and  switch  o b s e r v i n g the  f o r any  reason  voltage  ( o t h e r than be  sounder  provided  input  system  the  i s reconnected  tracks  protected  procedure  and  the  input  to drive  so  that  be  as  power s o u r c e .  use  i n p u t and cables  and  t h a t each panel  should  r e g u l a t o r to the  provided  oscilloscope  have  by  V which i s s u f f i c i e n t  to a suitable  check t h a t the  briefly  by  short  possible  to  voltage  correctly voltage  the will  the t r a n s m i t t e r .  i t  should  always  satisfactorily.  connect  Osing  caused  i t would s t i l l  the  meter i s d i o d e  connection  pitched  whine  failure)  v o l t a g e which  Connection  and  echo  When  output  panel  monitored  B or A r e s p e c t i v e l y  radio  27  regulator  be  the r e g u l a t o r f a i l  operate the  The  high-pitched  meter.  or  be  can  position  panel  exceeds  a  c o n t r a c t i o n s of the f l y b a c k i n d u c t o r .  voltages  in  then  emit  output  auxiliary  Listen  switch.and  power  power s e l e c t o r  instrument  fails  to  check for  i n s t r u m e n t s . t o the  indicators).  Make  switch i s set  to  polarity the  function  check  that  high  levels.  receiver,  regulator. (all sure 24  for  panel meter to  transmitter,  instrument operates normally  lamp  Arrange  voltages are at s u i t a b l e  connect . the  oscilloscope  satisfactory.  Carefully  source.  the s e l e c t o r  follows:  VDC. its  Check  instruments that  . the  . If  any  fuses  are  71  B.  F.  CONNECTIONS  Usually  the  r a d i o echo sounder  antenna.  In t h i s c a s e both the  connected  to the  A least port  antenna-via a  circulator three  ports.  1 e x i t s from  port  3.  transmitter from  port  pulse  i s radiated  received  The  construction  at the  i s not  system  an  about  25  power f r o m be  fed  directly  the  r e c e i v e r design  the  high  power  also  fully  protected  on  of the  s o u n d e r use  port  due  a 4 Kw  12  to  protection  by  an  from  exits from  pulse  The  2.  w from the antenna  t o the  received receiver.  transmitter  spike  reflected  circuitry  isolator  the  is plus  mismatch  In  be  is  isolation  impedance  would  exits  power  The  1 to 3  the  transmitted  reflected  event  capable of The  against i s simply  in  withstanding  transmitter  B.F.  of  into  been a n t i c i p a t e d , and  been i n s t a l l e d .  power  a circulator  is  being with  3).  h i g h - p o w e r B.F.  a  port  at  2  receiver input.  connections  t y p e N c o n n e c t o r s and from  antenna. The  the  b a c k i n t o i t (an i s o l a t o r  a dummy l o a d  operating  the  with  into  power  f e d back i n t o p o r t  has  be  power f e d  transmitted  T h i s s i t u a t i o n has  shock  single  device  into port  circulator,  antenna.  i n t o the  failure  a  r e c e i v e r must  switching  p o r t 3 which i s connected  reflections  receiver input.  reflected  to  so t h a t a b o u t  the  and  i s such t h a t  The  perfect i n that  dB  antenna c a b l e  All  1.  a n t e n n a and  The  will  provided  from the  T/B  power f e d  2 which i s connected  e x i t s from  any  and  i n t o port  power t h e n  only  passive  2,  with  circulator.  a  the  i s fed  transmitter  is  port  With  i s operated  hookmount  on  in  the  radio  echo  EG-8U o r EG-213U c a b l e s .  When  a h e l i c o p t e r an  additional  GE  72  connector antenna adapter  and  the  the  pilot GB  should  feed l i n e .  in  the  link  a GB  GB  be  installed  The  GE  to type  connection  of the  link  near  the  comprises  N male a d a p t e r .  effects  will  a type The  open  and  in  N female  friction  a "weak l i n k " .  h e l i c o p t e r i s f o r c e d to  connection  antenna  the to  coupling  In t h e e v e n t  jettison  break the  GB  the  that  antenna  cable link  to  the  antenna. The type  N  adapter  B.F.  connections  male-male connect  circulator. B.F. to The  adapter  the  Using  be  and  made  an  1 meter t y p e  port 2 of the cables  circulator  within  i t s e l f - uses connection  be  type  output  connection  on  antenna f e e d sounder hazardous.  the  line.  radiates Do  not  line.  the  cable  itself  to allow  Caution:  when  sufficient stand i n f r o n t  and  the  taped  antenna  the  cable  to  operating,  weak  free  end  to  o f the antenna  radio  be while  The  approach  the  the  the  connection  a tuning stub.  the  power  of  antenna.  f o r a convenient  connect  B.F.  1  a 5 meter  to  install  a  the r e c e i v e r  s h o u l d be  The  adapters  and  port  Connect  If required  antenna  to  Using  N right-angle  N cable connect  strain.  N "Tee"  articulated  the antenna feed  run  antenna  to relieve  two  can  the  and  follows:  o p t i o n a l type  t r a n s m i t t e r B.F. a  as  i n p u t t o p o r t 3 of the c i r c u l a t o r .  antenna r e f l e c t o r  by  should  link of  the echo  considered the  radio  echo sounder i s o p e r a t i n g .  BEMAINING BECEIVEB TO  In a d d i t i o n t o t h e  TEANSMITTEB CONNECTIONS  B.F.  connection  there  are  two  other  73  connections the  local  trigger  between oscillator  local  transmitter oscillator reference  SM4  t r a n s m i t t e r and t h e r e c e i v e r .  power,  the  other  oscillator  (L.O.)  power  and  i s  frequency-?locked  also  in  the  transmitter.  freguencies. to  The c o n n e c t i o n ,  the  sockets  120 MHz r e c e i v e r i n t e r m e d i a t e The t r a n s m i s s i o n circuitry.  capable  a  The  generated 120 MHz latter  of  trigger  "L.O." on  the received  5 V into  In t h i s  adjustable while  maintaining  a 50Q. l o a d .  This  signals  after  a second  RG-58 SMA c a b l e  transmitter  long  way t h e R.F. p u l s e l e n g t h a high  delays.  and " T r i g "  on/off  ratio  The c o n n e c t i o n  to sockets  a  transmitter  each  of the to  a  R.F. s i g n a l t o  i s generated i n the r e c e i v e r  medium power R.F. a m p l i f i e r a s w e l l a s g a t i n g  R.F. a m p l i f i e r .  provides  (I.F.).  I t h a s been p r e s e t t o 50ns p u l s e  driving  crystal  160mW o f L.O. power  freguency  pulse  i n the  made by a t t a c h i n g an RG-58  marked  m i x e r i n t h e r e c e i v e r which c o n v e r t s  the  transmission  f o r b o t h t h e 720 MHz L.O. a n d t h e 840 MHz  cable  logic  the  i s  to  t r a n s m i t t e r and t h e r e c e i v e r , p r o v i d e s  the  is  One i s  pulse.  The  carrier  the  marked  length pulse  and i s  triggers  the high  power  i s externally f o r detecting  i s made by a t t a c h i n g "PULSE  IN"  on  the  on t h e r e c e i v e r .  OSCILLOSCOPE CONNECTIONS  Five the  BNC c o n n e c t o r s  signals  Tektronix  required  on t h e r e c e i v e r f r o n t to  475 o s c i l l o s c o p e .  make  photographic  They have  been  panel  provide a l l  records marked  from  "T",  a  "A",  74  "Z",  "V",  following The  and  "E".  The  f u n c t i o n s o f each  paragraphs. connector  marked  "T"  marked  "Trig".  It  serves  latter  as  as  a  electrical  the  well  I-F.  amplifier-detector  connector  is  93 D.  bandwidth.  records  (X-Y  The  as  for  photos  "Z"  amplifier.  The  the  A  the  the  with  c a r r i e s the  and  of  SMA  a backup t r i g g e r  p r o p e r t i e s are i d e n t i c a l "A"  hHz  i s a twin  trigger  The  impedance 40  i s described i n the  connector  source  Its  "Trig".  unmodified the  video output  in  signal  s t a y s between 0 and  is  the  oscilloscope.  strip  signal  to  used  receiver.  for  a l l  of The  +3  V  with  "A-scope"  o f power v s . t i m e ) .  connector  I t i s normally  carries used  the  output  o n l y as a m o n i t o r  of  the  video  of  the  video  signal. The It  "V"  connector  carries  i s i d e n t i c a l i n nature  code  or  stream.  Both  intensity The used  grey  scale  can  t h e V and  of the "E"  the o s c i l l o s c o p e  be  called  "mixed v i d e o " .  Z s i g n a l except  momentarily  Z s i g n a l can  be  that  switched used  to  a  frame  i n t o the  data  modulate  the  phosphor b r i g h t n e s s .  connector  t o s c a n an  to the  a signal  carries  a s l o w l y v a r y i n g ramp w h i c h i s  intensity  modulated l i n e  screen.  This s i g n a l i s  trace  vertically  used  when  across  continuous  records are required. Connecting system  the  oscilloscope  r e q u i r e s f o u r BNC  follows.  Connect the  connector oscilloscope  on  the  trigger  cables  receiver  which "T"  oscilloscope s o u r c e on  into  the r a d i o echo should  output  be  to the  (lower  deployed  as  "external t r i g "  right).  "EXT", c o u p l i n g on  sounder  "DC",  Set slope  the on  75  positive, Connect Set  the  the  E  mode on the  Ch1  receiver  k  output at  to  the  2 V/div  oscilloscope  After  w i t h DC  THE  several  records  need be  are  done o n l y  the  flashing light  on  its  warmup c y c l e .  During  the  transmitter lamp w i l l  select that  on  Chi  the  on  the  20  MHz  (20  as  Set  The  at  the  on  input. Connect  Set  the  V output  Ch2 to  instrument) .  the  the  gives  taken  taken.  The  beginning  transmitter  and  the  the  At  the  procedure  operation.  this  period  before  of  indicates  which  oscilloscope.  that  i t  high voltage  end  any  of t h i s  is  supply  in in  warmup. p e r i o d  continuously. receiver.  source.  t i m e b a s e on  1 us/div Set  the  s i g n a l t o n o i s e and  better  signal the  oscilloscope  to  Polaroid is  now  On  noise,  up  oscilloscope  trigger level  vertical or  500  position  ns/div  bandwidth  to  resolution 100  camera t o set  the  Adjust the  Adjust the  ice thickness.  Attach  be  transmitter  vertical  d e p e n d i n g on  resolution).  input.  Connect the  must  be  power f o r the  the  expected  MHz  to  i s disabled.  stay the  steps  echogram i s s t a b l e .  midframe.  Ch1  coupling.  Ch2  of  knob".  BADIO ECHO SOUNDER  power f o r the  The  Turn  w i t h DC  (rear  A locks  oscilloscope  coupling.  Z-axis input  assembly  Turn on  the  V/div  11  SETUP  photographic follows  0.5  mode on  t o the  oscilloscope  A1.1.2 OPERATION OF  INITIAL  horizontal  output  attenuator at  attenuator the  "AUTO" and  for  MHz  the  so to  depending  100  MHz  or  requirements gives  better  oscilloscope.  A-scope  photographs.  76  O n l y one  a d d i t i o n a l i n i t i a l adjustment i s required  recording. signal to  S e l e c t Ch2  (set switch  three  the  t o GND),  graticule  signal to  as  vertical  adjust  divisions  source,  the  vertical  below  centre,  for  I-scope  uncouple the trace  Ch2  position  recouple  the  Ch2  DC.  A-SCOPE RECORDING  To  make an  S e l e c t Ch1 to  as  medium  Set the  A-scope  the  well  vertical  brightness.  s h u t t e r speed  (approximate). a  is  source.  Close at  frame  camera  s.  let  camera i n t h e  may  familiar  the  following  Adjust  the  1/60  Operate the  exposed  operator  p h o t o g r a p h use  the  procedure.  screen  brightness  onto  the o s c i l l o s c o p e .  the  aperture  u s u a l manner.  at  f:4  Getting  r e q u i r e s e v e r a l attempts before  with  the  required  the  brightness/aperture  combination.  Z-SCOPE RECORDING  In  this  mode i t i s p o s s i b l e t o use  make c o n t i n u o u s Adjust  the  records.  screen  S e l e c t Ch2  brightness  maintaining  signal  visibility.  the  scale  as  grey  Depressing the  grey  the  a  to the The  source  as  the the  vertical  may  setting  choose the  momentary "GREY SCALE" t o g g l e s w i t c h  scale into  the  video  signal.  T h i s shows up  to  source.  minimum b r i g h t n e s s  operator  for  P o l a r o i d camera  while  to  use  brightness. will as an  switch eight  77  step the  staircase  record  using  the  the rotary switch.  required  displayed  in  automatically "START" To  aperture  frame  a  frame  a t f:16. on  to  One m i n u t e i s  f o r each  typical.  Using  preset  t h e frame c o d e t o one l e s s  frame  number.  receiver.  first  The frame c o d e i s  The  the  close  speed  receiver  the  will  depression  the shutter  receiver. by  camera  a t "T" (time  of  one  onto  the  exposure)  and  r e l e a s e and d e p r e s s t h e  This and  action w i l l the  t h e "READY" lamp h a s r e l i t  This action closes the  the f i l m the  Press  increment  When  release again.  practice  the  s e t the shutter  extinguish.  removing  on  Select a duration  switch.  switch code  starting  octal  expose  "START"  ten  a t the l e f t of  increment t h e frame count a f t e r each  oscilloscope, the  the brightest step  up t h e r e c e i v e r as f o l l o w s .  "RESET" and "RUN" s w i t c h e s  than  the  with  screen. Set  the  starting  camera  cause t h e  "READY" press  lamp  the shutter  shutter.  After  f r a m e t h e c y c l e i s r e a d y t o be r e p e a t e d .  entire  p r o c e d u r e can be a c c o m p l i s h e d  to  With  i n l e s s than  seconds. Examination  following.  Each  exposing  first  picture.  This  of  an  I-scope  record  uses  will  reveal  s t a r t s a t t h e bottom o f t h e s c r e e n  t h e grey s c a l e , process  photograph  then  the  frame  1/16th o f t h e t o t a l  code record  into time.  the by the  78  A1.2 In A1.2)  THE  principle  i s simply  results stable  from  Jersey.  echo  R.F.  output  design  Its  sophistication  switching  overload-sensitive  and t h e i n s t r u m e n t by  power  Control  has been i n c l u d e d  and t o a i d p o s s i b l e  field  times, supply.  were p r o v i d e d  Microwave  The f o l l o w i n g i n f o r m a t i o n  to the design  transmitter (Fig.  power l e v e l , f a s t  of B r i t i s h Columbia  A1.2. 1 -POWER  sounder  oscillator.  and f o o l p r o o f ,  user i n t e r e s t  rights  radio  gated  i t s high  circuit  University  the  a  freguency  The  for  TRANSMITTER  f o r the  Co., here  New  solely  serviceability.  No  are implied.  SUPPLY  REGULATORS  The  input  transmitter. referenced transistor  power r e g u l a t o r s The  +26  t o Zener diode Q1  i s biased  transistor  Q2 t h e r e b y  regulator  (Fig.  transistor to  Zener  V  Q24 b e i n g  diode  D29.  regulator D1.  used  If  on which  pulling  A 1.4)  provide  i s  +26 V and +5 V output  the  (Fig.  output  increases  simple  the sink  shunt  as a v a r i a b l e c u r r e n t  the  A1.3)  is  voltage  down t h e o u t p u t v o l t a g e . a  for  current i n The +5 V  regulator sink  rises  with  referenced  FIG. A1.2  TRANSMITTER: PICTORIAL ID  VSAA-  VSAA-  R6  if  ri  k  R7  - L  C1  R10 02  R11  FIG. A1.3  D3  REGULATOR CIRCUIT  DIAGRAM  81  ENABLE O  •5VO  O  R51 \AA/—*  3  8  1  7  4  +5V  +5V Q  ^ R5|3  TIMING ,  1/3 SN5410  LIGHT O  017  SE555V  R55  R56  R57  1/3 SN 5410  RESET *26V  D10  14 R58  D11  !  R59  W V  Q18  SN7493A  1 /  1/3  g  D12  Df  R60  A/v\—  5  1  POWER  2  SUPPLY  10  1 SN7493A +5V  11  5  O  'I  •O +5V  10  11  2  I-  TIMING CIRCUIT  12  I H  SN5410  8  4=C66  •i  i|  12  SCHEMATIC  DIAGRAM  FIG. A1.4  82  WABM-UP TIMING  CIRCUIT  When power i s f i r s t voltage  power  filaments  supply  t o warm up.  applied  to  the  i sdisabled  t o allow time  A digital circuit  high v o l t a g e enable f o r approximately capacitor switched  C66  D12  ensure  hex  counter.  circuit lines  i s discharged  off.  As a r e s u l t  then  up t h e c o u n t  enable  vibration.  The  line  open  in  a NAND g a t e  counter. SN7493A counter count  SN7493A  Q18  to  be  diode SN7493  reset.  Reset  Q18 and t h e r e s e t  Q4  collector  hex'EO'  multivibrator  SE555V  output  At power-  i s in  astable  on p i n 3 d r i v e s a NAND  The o u t p u t on t h e  Q3  resistor  NAND  R56.  gate  drives  T r a n s i s t o r Q17  causing i t t o flash pulse i s  input  and  Q4  t o determine t h e ENABLE  and f o r c i n g  A low l e v e l  on and  inverted  again  ( p i n 14) o f an SN7493A  outputs  t h e ENABLE  level  goes  a high clock  from  t r a n s i s t o r -Q17  p a n e l lamp r e m a i n s  clock.  output p r o v i d e s a c l o c k pulse f o r the second The Q2,  counter.  cycle  i s l o w and t h e  panel timing l i g h t  a r e "NAND"ed  on  power-up  p i n 2 o f each  counters are  f r e q u e n c y . . The c l o c k  counter.  turns  on r e s e t  and d r i v e s t h e c l o c k  The  reaches  SE555V  and  front  a t t h e count  At  transistor  provides a start-up  t h e b a s e o f t r a n s i s t o r Q17 t h r o u g h  off  two m i n u t e s .  t u r n s on t r a n s i s t o r  a s an i n v e r t e r .  the  f o r the triode  t o a low l e v e l .  An SE555V t i m e r  drives  high  r e s i s t o r B60 and Zener  Thus a s power-up b o t h  a r e brought  g a t e used  level  the  ( F i g - A1.4) d e l a y s t h e  forcing  pull-up  a TTL h i g h l o g i c  relaxation  transmitter  of  the  level.  low  second  When t h e  resetting  the  i n p u t on t h e f i r s t  the multivibrator i s inverted  continuously.  on c o n t i n u o u s l y i n d i c a t i n g  At t h i s t i m e t h e the  end  of the  83  warm-up p e r i o d .  POWEB SUPPLY  All  power s u p p l i e s a r e c o n s t r u c t e d u s i n g  transformers. transistors these  DBIVEE  C u r r e n t s i n the primary  Q19, Q20,  Q21  and Q22  step-up/isolation  windings  (Fig.  are switched  A1.5).  Pulses to drive  t r a n s i s t o r s a r e d e r i v e d i n t h e power s u p p l y The  astable  basic transformer multivibrator  A1.6).  freguency  and a J-K  The Q and Q o u t p u t s  p u l s e s onto voltage  the bases  drive,  (1/2  of the f l i p - f l o p  cf transistors  and  transistors  driver.  i s determined  flip-flop  Q26 and  by  by an MC4324  SN5473)  (Fig.  alternately  enable  Q28  in  the  high  Q30 and Q32 i n t h e low v o l t a g e  drive. Duty c y c l e s independently SN54123.  for  high,  determined  The  simultaneously  the  two with  by  vibrator  B82  monostable  vibrators  state  Q31. and  E84  on  At t h i s  When  changes  time  both  supply  vibrators are  are in  drives  a  triggered  i s  preset  The o u t p u t  The by  of this  h i g h and g o e s low when t h e v i b r a t o r  both  transistors  Q30  and  down e m i t t e r - f o l l o w e r t r a n s i s t o r s transistors  no c u r r e n t f l o w s i n t h e p r i m a r y  power  drives  i n t h e J-K f l i p - f l o p .  and c a p a c i t o r C78.  low  pulling  voltage  monostable  ( p i n 4) i s n o r m a l l y  is-triggered. switched  and  low  two  p u l s e l e n g t h f o r t h e low v o l t a g e resistors  and  Q32  are  Q29 and  Q19 and Q20 a r e s w i t c h e d o f f winding  of the  low  voltage  transformer. At t h e end o f t h e m o n o s t a b l e c y c l e t h e o u t p u t  o f one o f t h e  TIMING  26V POWER SUPPLY DRIVER  TIMER  + 5V  LIGHT  POWER  RESET  ENABLE  SUPPLY  WIRING DIAGRAM  K—j COLLECTOR BIAS  D13  D15  C67 R61  Dtt  to MON.PIN-H  D16  A 26V  2T  4  D17  2T 66T  £7  FIL.1  [ 6T  FIL.2  i  - w v  R63  R62  0 18  C69  D.19  AAAH  O  CATHODE BIAS  .••91 V  C70  to MON. PIN - F D20  D 21  • 5V  4000 V AMP. 2  R77 -AAA/—  2000 V  O R 78  R79  LXQ23 1r80  O AMP. 1 R81  AAAv— D26 R76  to MON.PjN-G. —  —  H.V. ADJUST  •  FIG. A1.5  85  • 5V R85 PRIMARY R72 D27  • 5V  R73 D28  R74 13MC4324 12-  D29  H  Q24 ^ - * 5 V  11  1  -LC76  U  SN5473 12! 11  6  C78  7  DRIVER  >R87  SCHEMATIC C80  •5V  DIAGRAM  Q27 -O  Q28  3  SUPPLY  — i f —  O-  1  POWER D30  R88  •5 V  8  SN5A123  C77  •—I—•  tcl  9  Q25  • 5V  • 5V  H.V AD J O -  C79  Q26  9 7  •R86  SN5410  A -O  D31  R89  ?R90  B  R92  C -O  •5V  ENABLE  —O  R91 SN5410  C 81  Q29  1 3  Q30  A •5 V  D32  <R93  COLLECTOR BIAS —O  13  R94  €82  R95  —Ih—  Q 32  D33  0 31  <R96  FIG A1.6  86  NAND g a t e s  d r i v e n by t h e m o n o s t a b l e  off  one o f t h e t r a n s i s t o r s  or  Q31  switching  variable  transformer voltage after and  R82  which  without  varies varies  the the  varying the  f o r the collectors s t a r t - u p from  derived  high in  voltage  controlled  peak  output  resistor  Q29  Adjusting  time  output  of t r a n s i s t o r s  of  voltage  the of the  voltage.  Source  Q25, Q27, Q29 and Q31,  R61, comes f r o m d i o d e s  voltage the  timer,  supply, by  supply  i s turned  goes low.  the  high  D13 and D14  too  on  the voltage  the  supply The h i g h  of  variable  A1.7) R78 a p p r o a c h e s +5 V and t r a n s i s t o r effectively  standby voltage  The supplies  voltage  is  supply,  tries  resistor  Q23 s w i t c h e s  shown t w i c e  t o go (Fig.  off.  i n t h e two  i n c r e a s i n g the monostable c y c l e time  time. power  voltage output  LOW  cycle  This  i n c r e a s e s the s e r i e s r e s i s t a n c e to m u l t i v i b r a t o r p i n  (R81 and R75 a r e one r e s i s t o r ,  drawings),  duty  I f t h e + 4 KV s u p p l y  tap  line,  I n t h e same manner as i n t h e  a monostable v i b r a t o r . regulated.  high  on when t h e ENABLE  voltage  however, i s f e e d b a c k  6  Q19 o r Q20.  standby  RMS  transistor  c a p a c i t o r C67. The  low  Q30 o r Q32 and t h r o u g h  on one o f t r a n s i s t o r s  resistor  multivibrator,  v i b r a t o r goes l o w , s w i t c h i n g  This  transformer  the  primary  and r e d u c i n g t h e  power a v a i l a b l e t o t h e h i g h winding  forcing  the  high  t o drop.  VOLTAGE  low  reduces  separate  SUPPLY  voltage supply  (Fig.  A1.5)  and a +91 V c a t h o d e b i a s s u p p l y .  provides  two f i l a m e n t  The f i l a m e n t s u p p l i e s  87  0  H.V. ADJUST OVERLOAD ADJ.  POWER SUPPLY BOARD POWER  IN  RIGHT  H.V. CAPS  SIDE  INPUT-© CATHODE MODULATOR OUTPUT  LEFT TRANSMITTER: (NOT  SIDE INTERNAL  TO  SCALE)  FIG. A1.7  LAYOUT  88  are unregulated  after  t h e two t r i o d e s  are controlled  The using The  cathode  diodes  supply  R62.  b i a s supply  D15,  i s shunt  Excessive  t h e + 26  V regulator.  Filament  by v a r i a b l e  resistors  includes  a  full  power wastage i s a v o i d e d  R2 and R3.  wave  D16, D17 and D18 and s t o r a g e r e g u l a t e d by Z e n e r d i o d e  currents to  rectifier  c a p a c i t o r C69.  D19  and  resistor  i n a manner d e s c r i b e d  previously.  HIGH VOLTAGE SUPPLY  The  high  voltage supply  supply  f o r the f i r s t  final  triode  D23,  amplifier.  The  +4 KV s u p p l y  amplifier  A 1.5}  provides  +2  wave r e c t i f i e r  uses f o u r diodes and s t o r a g e  adds v o l t a g e d o u b l e r  s t o r a g e c a p a c i t o r C71.  a  KV  and a +4 KV s u p p l y f o r t h e  The +2 KV s u p p l y  D24 and D25 i n a f u l l  C74. and  triode  (Fig.  The h i g h v o l t a g e  D22,  capacitor  d i o d e s D20 and D21 supply  regulation  I f the l o a d  dissipation  was p r e v i o u s l y d e s c r i b e d . The  supply i s over-load protected.  increases  f o r any r e a s o n  sense  resistor  Zener  diode  RESET  line  reinitiating overload  the (negative)  R70 a l s o i n c r e a s e s .  The drop  D26 and r e s i s t o r R76) t h e drops  too  low  t h e s t a r t - u p sequence  voltage across current  RESET  transistor with  down  voltage. Q18  ENABLE l i n e  l e v e l i s p r e s e t by v a r i a b l e r e s i s t o r  i  pulls  R71.  (through If  switches high.  the off The  89  A1.2.2 The R.F.  modulator c o n t r o l s s e p a r a t e l y the gain  amplification.  state  the  The  pulse  o f two s t a g e s o f  a m p l i f i e r gates  t h e 20 H  R.F. a m p l i f i e r , and t h e c a t h o d e m o d u l a t o r g a t e s  triode  amplifier.  50  The (Fig.  Both modulators take  TTL l e v e l  PULSE  incoming  pulse  from  so t h a t  i s again  power  input  the  first  s i g n a l s from  "PULSE IN" s i g n a l .  pulse  i s  buffered  A1.8) t h e n a m p l i f i e d / i n v e r t e d i n  adjusted  their  solid  AMPLIFIER  constructed  a  MODULATOR"  transistors the pulse  Q8  and  length  by a DM8830 l i n e d r i v e r , a  push-pull  Q10.  cannot  Resistor  exceed  a m p l i f i e d / i n v e r t e d by t r a n s i s t o r  switch  f o r the s o l i d  amplifier R71 i s  200ns.  The  Q_9 w h i c h a c t s a s  s t a t e R.F. a m p l i f i e r .  The  output  v o l t a g e s w i n g s between 0 and +25 V.  CATHODE MODULATOR  The pulse  cathode modulator  amplifier.  transistor length pull  Q6.  to  200  The  incoming  push-pull  A 1.9)  i s very  pulse  i s a m p l i f i e d / i n v e r t e d by  R e s i s t o r R16 i s s e t t o l i m i t ns.  The p u l s e  amplifier constructed  additional  (Fig.  from  the  to the  maximum  pulse  i s a m p l i f i e d / i n v e r t e d by a p u s h t r a n s i s t o r s Q3, Q4 and Q7.  emitter-follower transistor a m p l i f i e r t o boost  similar  t h e source  The  Q4 h a s been added t o t h e current drive  capability  90  WALL 26 V FROM R.F.  'R23 < R24  R22  PULSE  IN  J8 J9 TO CATHODE MODULATOR  R25  D5 1 2 3  C11  C12  Ml—I '  U  DM 5 8830 6 7 8  C10  R26  1  C13  R27  U  C16  R30 HAA»  If  TO  09  R31  C17  '  AMP.  J7  D7  R32 C18  D6  R.F.  R33  PULSE  AMPLIFIER  CIRCUIT  DIAGRAM FIG. A1.8  AMP.  X C3 I  + 5V R12 : L  SR13 CATHODE  C5 1C6  C4  T f  D4  C8  J10  04  RU  H>l—  • R15  >K  R17  R19 -  C9  05  1  f R20 .07  CATHODE MODULATOR  CIRCUIT DIAGRAM  FIG. A1.9  PULSE  92  to  t r a n s i s t o r Q5.  amplification. collector  Transistor Q5  load  i s  Q5 i s t h e  a high-gain,  including  resistor  final  stage  of  pulse  high-power t r a n s i s t o r R1  and  the  first  with  triode  cathode.  A1.2.3 THE £.3?.  CHAIN  The  derives  H.F.  chain  f r e q u e n c i e s by m u l t i p l y i n g oscillator. at  840  of  c a n d e v e l o p 4 KW  120MHZ OSCILLATOR-AMPLIFIES  The  basic  120 MHz  120 MHz  first  -of  Q14.  X6, X7  operating  tuned  a  oscillator  120 MHz  crystal  o u t p u t power i n t o  frequency i s generated  crystal  oscillator  c l a s s AB.  R.F. a m p l i f i c a t i o n  uses s t r i p l i n e  50  by a TTL  (Fig.  A1.10).  u s e s t r a n s i s t o r Q13  This  i s followed  by  as a three  u s i n g t r a n s i s t o r s Q16,  o p e r a t e c l a s s C.  The f i r s t  components i n i t s t u n e d  Q15  class  circuit.  MULTIPLIERS  120 MHz  D9-  isolated  modular  A l l three a m p l i f i e r s  C amplifier  The  reference  s t a g e o f R.F. a m p l i f i c a t i o n  amplifier,  stages  diode  the f r e q u e n c y  THE  tuned  and  chain  c a r r i e r and l o c a l  MHz.  compatible The  The  the  output  (Fig.  power  A1.11).  by s t r i p l i n e  drives  the  nonlinear  varactor  The s i x t h and s e v e n t h h a r m o n i c s a r e  tuned c i r c u i t s .  The  sixth  harmonic  is  26 V  R39  C37  AAA/ D8  AAAr  f C39  R40  R41  SL8  C55  R42  zz/  X  R43  R44 C41  -QT3  LU R48^C46  7|C47  C42^  I^MT "  R48  AAAr  C50  Q16 _ I _ C 4 9  )  J-C43  I  KL18  C48.  L16  R45  1  >L9  L10 C40  LEAD R46  LU  ' LEAD  Q15  R.F.  C51-  OUT  C53  R 49  120 M H z  OSCILLATOR - AMPLIFIER  CIRCUIT  DIAGRAM FIG.A1.10  V  C56  C57  L21  L20  x7  C58  MULTIPLIER  R.F. OUT  J4 L23  J ^  C  5  9  X  C  6  °  -  D9  C63  R50  C61  — C62  J3  *6 MULTIPLIER 720 MHz  1 x6. *7  MULTIPLIER  C64  BP. FILTER  -  CIRCUIT DIAGRAM  FIG. A1.11  TO L.O.  95  further the  filtered  720 MHz  oscillator  840 MHz  output  20 W.  local  first  Q12  (Fig.  stage  by  amplification  A1.12).  switching  The  pulse  the c o l l e c t o r  from  state  R.F. a m p l i f i e r  the t r i o d e  amplifier  section  section  by a  isolator. high-power  first  This  adjusting  R.F. a m p l i f i e r  triode  triode  centre  The  the  and  It i s isolated  cathode.  by  Q11  power of t h e s o l i d  microwave c a v i t y  The  the  seventh harmonic from t h e m u l t i p l i e r i s f u r t h e r  gates  The  the  provides  point  on and o f f .  The  ferrite  This  t h r o u g h two s t a g e s o f t u n e d common-base  amplifier  is  mW.  At t h i s  AMPLIFIER  transistors  current  bandpass f i l t e r .  power t o t h e r e c e i v e r .  amplified using  a 720 MHz  power l e v e l i s 160  840MHZ R.F  The  by  amplifiers.  amplifier  by  switches the t r i o d e  (Fig.  uses  two  The c a t h o d e m o d u l a t o r  gates  switching  connector.  by  a ferrite  on t h e cutoff.  amplifiers  are set  configurations.  outpu>t pawer of t h e R.F. c h a i n  isolated  t h e DC l e v e l  o u t o f and b a c k i n t o  f r e q u e n c i e s and Q» s o f t h e t r i o d e their cavity  A1.13)  i s 4 KW.  It  is  i s o l a t o r and a t t a c h e d t o t h e R.F.  again output  Y  J7  + 26 V IN  WALL TO  PULSE AMR  'HP  C19  R34 1 T  R35  " C  2  '  '  C20 +1  I L1  C22  C23  H i -  C2U ) R.F.  L3  IN  (from x7)  r  C 2  _. v C29  C27  011 r  ~  if  «<L4  N// C31  840 MHz  R.F.  V  /FC32  AMPLIFIER  G 3 3  R.F. OUT  L2  V  \  iL5  CIRCUIT  Q12 _L  C28 /  . JL  TO  ISOLATOR  J6  C34 71- 7 T C 3 5  DIAGRAM  FIG. A1.12  97  L.O.  J3  1  W v  TRIODE AMP. 8757 or  R.F OUTPUT  r~  30W PEAK  |  BP. J6  4 W  DM20-28  FILTER  8874 A  720MHz  Y641  J4 84 0  H  1.5A  '  1. 3 A  2000 V  1  840  MHz  x 7  MHz  x 6  AMPLIFIER MULTIPLIER  MULT I  L CATHODE l _  «1 MOD.  91 V R2  R  LU  LU  26V  • 30 VDC  5A  REGULATOR  > I  to <  J2  _  "1 J 1  3  LU  A  • 5V  CN  GO  PULSE  LIGHT  MHz  SOURCE  POWER  MAIN POWEI  120  N  <  o  TIMING  B12-28  OSM  B3-28  SUPPLY  TIMING LIGHT  TRANSMITTER  BLOCK  DIAGRAM  2N3866 OSCILLATOR 2N3866  FIG: A1.13  j  98  Table  A l : Power C o n n e c t o r  Pin Designations  DC POWEB INPUT I  +30  J  -  Volts  Return  MONITOR TEST POINTS A Spare B, C F i l a m e n t  #1  D, E F i l a m e n t  #2  F  HV  Monitor  G Reset H Bias  Line Voltage  99  Table  A2: T r a n s m i t t e r :  Y518 C a v i t y  Triode  Y641 C a v i t y  Triode  840 MHz I s o l a t o r ,  5 KW Peak  840 MHz I s o l a t o r ,  30w  Integrated  Peak 120 MHz  Oscillator  Circuits:  SN5410 TTL T r i p l e  3-NAND (x3)  SN5473 T T L D u a l J-K  Flip-flop  SN7493A T I L 4 - b i t B i n a r y  Counter  SN54123 T T L D u a l M o n o s t a b l e MC4324 TTL D u a l V o l t a g e SE555V MOS  R e q u i r e d M a j o r Components  Linear  Timer  (x2)  Vibrator  Controlled Multivibrator  100  Table  A3: T r a n s m i t t e r :  D i s c r e t e Components P a r t s  Q1 MPS-U06  Q23 2N2907  Q2 2N5883  Q24 MPS-U57  Q3 MPS-U57  Q25 MPS-U07  Q4 2N3009  Q26 2N4264  Q5 2N5430  Q27 MPS-007  Q6 2N4264  Q28 2N4264  Q7 2N3009  Q29 MPS-007  Q8 MPS-3640  Q30 2N4264  Q9 2N3720  Q31 MPS-007  Q10 2N300 9  Q32 2N4264  Q11 D5-28B  D1 1N5251  Q12 DM20-28B  D2  1N4007  Q13 2N3866  D3  1N4007  Q14 B12-28  D4  1N914  Q15 B3-28  D5  1N5231  Q16 2N3866  D6  1N5253  Q17 2N2222  D7  1N4732  Q18 2N2222  D8  1N5240  Q19 2N3055  D9  VAB-810  Q20 2N3055  D10  1N4007  Q21 2N3055  D11  1N5246  Q22 2N3055  D12  1N5230  List  TABLE  A3 CONT.  D13  1N4007  C5  lOOpfd  D14  1N4007  C6  4.7pfd  D15  1N4007  C7 0.05 u f d  D16  1N4007  C8 0.1 u f d  D17  1N4007  C9 0.0033 u f d  D18  1N4007  C10 0.1 u f d  D19 1N-5377  C11  D20  USE-60  C12 27 u f d , 35 V  D21  USE-60  C13  D22  100S8F  C14 0.0033 u f d  D23  100S8F  C15 0.1 u f d  D24  100S8F  C16 0.1 u f d  D25  100S8F  Ci17 0.0022 u f d  D26  1N4754  C18 0.01 u f d  D27  1N4007  C19  D28  1N5234  C20 50 u f d , 50 V  D29  1N5230  C21  D30  1N914  C22 2 2 p f d ,  D31  1N914  C23  D32  1N914  C24 0.001 u f d , f e e d t h r o u g h  D33  1N914  C25  0.001 u f d , f e e d t h r o u g h  180pfd  0.001 u f d , f e e d t h r o u g h  50 u f d , 50 V feedthrough  0.1 u f d  7.5pfd  C1 27 u f d , 35 V  C26 1-10pfd,  variable  C2 100 u f d , 5 V  C27  1-10pfd,  variable  C3  C28  390pfd  C29  1-10pfd,  10 u f d , 8 V  C4 0.1 u f d  variable  TABLE A3 CONT. C30  1-10pfd,  variable  C55  200pfd  C31  1-10pfd,  variable  C56  75pfd  C32  1-10pfd,  variable  C57  0.1-3pfd,  C33  7.5pfd  C58  1-10pfd,  C34  1-10pfd,  variable  C59  95pfd  C35  1-10pfd,  variable  C60  300pfd  C36  0.001  ufd, feedthrough  C61  1-10pfd,  variable  C37  0.001  ufd, feedthrough  C62  1-10pfd,  variable  C38  50  C63  0.1-3pfd,  C39  0.001  C64  1-10pfd,  C40  27pfd  C65  22 u f d , 20 V  C41  24pfd,  C66  15 u f d , 35 V  C42  Selected  C67  50 u f d , 50 V  C43  60pfd  C68  22 u f d , 35 V  C44  65pfd  C69  18 u f d , 150  V  C45  450pfd  C70  18 u f d , 150  V  C46  20pfd  C71  0. 1 u f d , 5 KV  C47  0.001  C72  22 u f d , 35 V  C48  20pfd  C73  22 u f d , 35 V  C49  1-10pfd,  C74  0.1  ufd, 3  C50  51pfd  C75  3.9  ufd,10 V  C51  1-10pfd,  C76  0.015  C52  270pfd  C77  910pfd,  C53  0.001  C78  9 1 p f d , 20 V  C54  26pfd  C79  3.9  u f d , 50 V ufd, feedthrough  selected  ufd, feedthrough  variable  variable  ufd, feedthrough  variable variable  variable variable  KV  u f d , 100 V 20 V  u f d , 10 V  103  TABLE A3 CONT. C80 3.9 u f d , 10 V  L23  C81  R1  3.9 u f d , 10 V  RF choke 150 0.5w,  10%  C82 3.9 u f d , 10 V  R2 0103 Ohmite 3  12w  L1  RF c h o k e  R3 0103 Ohmite 3  12w  L2  3 Turns  R4 2.25  , 12w  L3  2 Turns  R5 2. 25  , 12w  R6 2. 25  , 12w  L4 3.5 L5  Turns  1 Turn  R7 200 v a r i a b l e  L6 BF c h o k e  R8 4.7, 12w  L7  8 Turns  R9 4.7,  L8  6 Turns  R10 200 0.5w,  L9 8 T u r n s  12w 10%  R11 62 0.5w,  10% 10%  L10  3 Turns  (leads)  B12 56 0.5w,  L11  3 Turns  (leads)  B13 150 0.5w,  L12  2 Turns  B14  L13  3/4  B15 500 v a r i a b l e  L14  5 3/4  L15  3 Turns  R17 470 0.5w,  10%  L16  0.02 uh  R18 470 0.5w,  10%  L17  6 Turns  R19 270 0.5w,  10%  L18  8 Turns  R20  L19  Selected  R21 330 0.5w,  L20  0.02 uh  R22 56 0.5w,  L21  0.0058 uh  R23 1800 0.5w,  10%  L22  0.022 uh  R24  10%  Turns Turns  10%  Selected  B16 2K v a r i a b l e  10 0.5w,  10% 10% 10%  1800 0.5w,  TABLE A3 CONT. E25 270 0.5w, E26  1 0.5w,  10%  10%  E27 470 0.5w, E28 2K B29 500  10%  variable variable  B50  Selected  B51  1K 0.5w,  E52 68K 0.5w, B53  1K 0.5w,  B54  68K  1K 0.5w,  100 0.5«, 10%  B55  E31  1K 0.5w,  E56 680 0.5w,  E32 330 0.5w,  10%  E33 510, 5%, E34 0.39,  2w  wirewound  E35 33 0.5w, B36  10%  B57  1.2K  10% 10%  0.5w,  E30  10%  10%  10% 10% 10%  0.5w,  10%  E58 22K 0.5w,  10%  B59  47K 0.5W,  10%  B60  4.7K  270-430 BH8-5W  0.5w,  10%  22K 0.5w,  10%  B61  E37 22K 0.5w,  10%  E62 27K,  B38  22K 0.5w,  10%  E63 470 0.5w,  E39 22K 0.5w,  10%  B64 4.5M  0.5w,  10%  E40 12K 0.5w,  10%  B65 4.5M  0.5w,  10%  B41  10%  B66  390 0.5w,  2w  2M 0.5h,  10%  10%  R42 68 0.5w,  10%  B67 2M 0.5w,  10%  B43  10%  B68  2M 0.5w,  10%  B69  2fi 0.5w,  10%  B70  1200  68 0.5w,  B44 5.6K B45 6.8  0.5w, 0.5w,  10% 10%  5w  B46  10 0.5w,  10%  B71 89PE 5K  B47  10 0.5w,  10%  B72 2.7K  r  0.5w,  E48 270 0.5w,  10%  B73  B49 220 0.5w,  10%  B74 91T 20K,  42  r  variable 10%  25w variable  TABLE A3 CONT. R75 91T 20K, v a r i a b l e  R86  100 0.5w,  R76  R87  1K 0.5w,  R88  100 0.5w,  R89  1K 0.5w,  10%  R90  10 0.5w,  10%  R91  100 0.5w,  variable  R92  10.0.5w, 10%  R82 91T-20K, v a r i a b l e  R93  1K 0.5w,  R83  10K 0.5w  R94  100 0.5w,  R84  5.6K  R95  1K 0.5w,  10%  R85  10 0.5w,  R96  10 0.5w,  10%  1K.0.5W, 10%  R77 4.5M  3w  R78  89PR-25K, v a r i a b l e  R79  1K 0.5w,  10%  R80 47K 0.5w,  10%  R81.31T-20K,  Other  .  f  10%  0.5v, 10% 10%  Components:  2 Toroidal 1 720 MHz  Transformers Bandpass  1 30 V, 5A C i r c u i t  Filter Breaker  1 28 V, T u n g s t e n P a n e l Lamp  .  10% 10% 10%  10%  10% 10%  106  A1.3 The includes  THE  RECEIVER  receiver for all  independent  the  frequency  video  amplifier.  photographic are  The  the  their  will  required  part  second  of  the  latter  (and  sounder to  (Fig.  perform  two  receiver i s  A1.14) basically  the  split  d e s c r i p t i o n s have been  all  transmitter  providing  since future  R.F.  includes  both  capability.  certainly  A1.3.1 THE  part  t o t r i g g e r the  recording  independent  sounder  One  echo  actual  r e c e i v e r - a heterodyne r e c e i v e r , detector  required  oscilloscope,  radio  circuitry  functions.  radio  circuitry  the  Since  versions  the  and  digital  and  to c o n t r o l  a  display  these of  two  the  these functions  an and  functions  radio  i n t o two  echo units)  separated.  CHAIN AND  VIDEO  AMPLIFIER  A1.3.1.1 PHYSICAL DECRIPTION The  RF  converting  components; a I.F.  diode  and  limiter,  a m p l i f i e r - d e t e c t o r and  (PAD'S).  A l l of  (the  module, s e e . F i g .  RF  receiver  by  the  removing  amplifying mixer,  two  I.F.  includes  s i x modular  filter,  logarithmic  6 dB.passive attenuating  components a r e A1.14)  the.four  chain  contained which can  retaining  in a be  screws  devices  l a r g e r module  removed f r o m around  the  the RF  inputs. The chain  video  a m p l i f i e r i s the  which i s not  components  as  bias  modular and  only  since gain  it  component o f t h e  RF-video  is  used  with  discrete  controls.  The  video  amplifier  FIG. A L U RECEIVER  PICTORIAL DIAGRAM  o  108  shares  space  converters ±15  VDC  on  a  for  the  Two  video  for  converter  and t h i r d  speed  amplifier  voltage  required  trigger  circuit  board  and t h r e e v o l t a g e r e g u l a t o r s .  circuitry.  high  printed  the  TTL  IF  and by t h e f r o n t  these  to  amplifier-detector.  circuitry panel  DC-DC  One c o n v e r t e r p r o v i d e s  reduce  regulator provide  logic  two  and +15 V f o r t h e CMOS l o g i c  regulators  log.  with  +5 VDC  used  ±12 VDC  The  required  second by  the  to drive the transmitter  displays.  A1.3.1.2 CIRCUIT DESCRIPTION  R.F.  CIRCUITRY  This  description  input.  Refer  against  to  traces the signal  figure  allows  any  unattenuated.  excess  of  50 mW  limiter  normally  either  because o f a d i r e c t  power  overloads  before  diode  The  in  diode  i n excess  to  as  RF  (DL1).  t o pass to the  The  through i t limiter  in  Saturation of the  transmission  occurs  wave between two a n t e n n a e o r b e c a u s e  the  antenna  limiter  is  w h i l e o p e r a t i n g with  a  mW  RF  the  input i s protected  by t h e l i m i t e r . time  from  limiter  50  feed  energy  saturated  will  back  capable  o f 4 KW i n t h e e v e n t  achieves  RF  Any power a p p l i e d  0.1 e r g o f h i g h l e v e l i t  up  o c c u r s each  a cable f a i l u r e  than  state  i s absorbed  reflected  circulator.  or  The  signal  effectively  of  A1.15.  o v e r l o a d by a s o l i d  limiter  starting  through  of  withstanding  of a c i r c u l a t o r a single  antenna.  pass through  state.  The  the  failure Less  the l i m i t e r  diode  limiter  >  RF  IN  DIODE  RF  LIMITER DL 1  N  ^  MIC S  M  MIXER M  A  1  IF  IF  BANDPASS FILTER  t  BP 1  1  LO  >  L O IN 6 dB P A D  6 dB P A D  SMA  VIDEO OUT  > —  e  4>  SMA  L O G IF  -  AMPIFIER A  SMA  + 12v  RF  MODULE;  1  •G-  SMA  -12v  CONNECTION  DIAGRAM  FIG. A1.15  110  requires  100ns t o r e c o v e r from  From balanced the for  the  diode  saturation.  limiter  miniature integrated  t h e BF s i g n a l p a s s e s circuit  mixer  to a double-  (M1) w h i c h  converts  s i g n a l t o t h e 120 MHz i n t e r m e d i a t e f r e q u e n c y  (I.F.)..  Power  t h e c o n v e r s i o n i s p r o v i d e d by t h e t r a n s m i t t e r  v i a the  front  panel  local  level  from  oscillator  the transmitter  attenuation required mixer  reduces  50  limiter both  level mW  (+6 dBm).  The  9.3  At t h i s  level  level  to  dB  fraction  I.F. s i g n a l  The c o n v e r s i o n at  filter  limiter  input  power.  power o f t h e d i o d e is  limited  by  t o about  4 mW  p r o d u c t power l e v e l  i sa  eliminates  level.  filter  any v i d e o  as w e l l as removing the mixer.  The 1 dB  to the  feedthrough  conversion  products  The 3 dB p a s s band o f t h e  The f u l l  filter  characteristic  is  i n F i g u r e A1.16. I.F. amplifier Specifically  airborne state  from  EF  and t h e d i o d e l i m i t e r  i s 99 MHz t o 141 MHz.  logarithmic  of  passive  The  of  i n the  BF l e v e l s .  attainable  a  dB  loss  passes through  o v e r t o n e s coming from  receiver.  low  +8 dBm  12  (+10 dBm), t h e l e v e l  I . F . power  and  The  10 mW  i n p u t power  dBm) .  of the fundamental  t h e diode  reproduced  (+22  the d i s t o r t i o n  from  range  level  mW  The L . 0 .  (+17 dBm) i s t h e maximum o u t p u t  I.F. a m p l i f i e r .  solid  160  i s approximately  L.O. power  significant  for  is  t h e maximum I . F . power l e v e l  the  filter  connector.  L.O. i n p u t .  approximately  compression Since  the  a t t h e mixer  is  (L.0.)  radar hybrid  is  the  central  component  d e s i g n e d by BHG E l e c t r o n i c s s y s t e m s i t was f a b r i c a t e d  technology.  compression -70 dBm t o +10  I t s key  characteristic dBm  (Fig.  Lab.  using thin  feature  with &1.17).  of the Inc. film  i s i t s  a u s e f u l dynamic The  amplifier  111  i  1——i  1  1  FREQUENCY  FIG.A1.16 I.F FILTER  1—~~i  r  (MHz)  BANDPASS CHARACTER  oO°° oooooooooooo  -80  I  I  I  I  -70  -60  -50  -40  I.F FIG. A1.17  INPUT  1  1  -30  -20  POWER  1  -10  AMPLIFIER  AT  120 MHz  1  10  (dBm)  CONTINUOUS WAVE CHARACTERISTIC I.F.  1  0  OF  LOG.  J  20  113  provides signal, to  a detected varies  2.84  V at  from +10 70  bandwidth  is  40.1  amplifier  output  DC  amplifier  power.  EF  dB  and  V a t an  of  a  risetime  VDC  provided  60  the  to  centre  The  less  the  mA  -12  of  VDC  supply  I.F.  amplifier  (100  120  20  BF  power  dBm  video  i s within  than  and  basic  amplifier  freguency  component i n t h e at  on  accuracy  range.  is  only  s i g n a l , the  l e v e l o f -70  logarithmic  at  i s the  This  I.F.  dynamic  MHz  generated  are  signal.  The  I t u s e s +12  voltages' are board  0.56  dBm.  o v e r more t h a n  I.F.  output  -  pW)  ±1  dB  3  dB  MHz.  The  ns.  The  module  requiring  at  mA.  130  video via  Both  amplifier  jumpers to  the  module. The  front  basic  video s i g n a l i s l e d  panel connector  video  amplifier  signal  for  The The  operational  bandwidth V us  - 1  amplifier bias  .  of  (required  the  amplifier.  to  ±15  amplifier.  an  the  video a m p l i f i e r  MHz  the  (Figure  amplifier  used  amplifier  here  excels and is  C5)  which  and  at  the  configured 475  E49  amplifier is  on  Brown  output  Z input) .  i s the  gain  same  video  bandwidth. 3400A),  having  an  full  rate  of  inverting  E48  is  adjustment  board  a  a  i s drawn f r o m t h e the  The  recording.  slew as  a  intensity,  i s a large  t h i s task  both  input.  phosphor  (Burr  an  Tektronix  Power f o r t h e  converter  jumpers t o  f o r continuous photographic of  30  by  the  oscilloscope  amplifier,  The  adjustment  VDC  of  amplifier  hybrid  to  coaxial  A1.18) i s n e e d e d t o c o n d i t i o n  requirement  monolithic  1000  and  image s u i t a b l e  prime  power  (Fig.  modulation  making t h e  (V)  by  24 as  the of VDC the  VIDEO  OUT  115  POWEB SUPPLY  The ±12  receiver  V and +5 V.  the  ±15VDC  output  12  the  24 V  to  current limiting  are  regulators,  provides f i v e  derived  from  goes  into  200mA  effect.  maximum  The  ±12 V  t h e ± 1 5 V s u p p l i e s by two t h r e e p i n  a 78M12 f o r t h e +12 V s u p p l y  +5 V  converter,  two  supply  with  constructed  resistors  switching  uses a separate  a maximum o u t p u t  from  alternately  and a 79M12 f o r t h e  -  results L1.  may  level. level  o f 1 A.  An a s t a b l e  in  a  off  transistors  pure  AC s q u a r e  The o u t p u t  vary from  square  control  recording modulated  of  the  areas:  the  This  in  a  full  p o i n t t h e DC  echo  logic  the  supply  a t 1 A.  circuitry  f o r the sounder  phosphor.  generation  drops  CIBCUITBY  necessary  radio  oscilloscope  At t h i s  goes i n t o e f f e c t  of the d i g i t a l  signals  Q4.  +7 V t o +9 V dependng on t h e i n p u t power  Current l i m i t i n g  function  and  wave i s r e c t i f i e d  by c a p a c i t o r C10.  A1.3.2 BECEIVEB DIGITAL The  Q3  clock to  wave on t h e p r i m a r y o f  A t h r e e p i n r e g u l a t o r (7805, TO-220) t o +5 V.  DC-DC  oscillator  (B45 and B46) p r o v i d e s a 400 Hz b i p h a s e  wave b r i d g e a n d f i l t e r e d voltage  discrete-component  two NOB g a t e s , two c a p a c i t o r s (C11 and C12) a n d  s w i t c h on and*  transformer  two  28 V i n p u t , w i t h  provides  V supply. The  the  DC v o l t a g e s , ± 1 5 V,  A B u r r - B r o w n model 528 DC-DC c o n v e r t e r  from  before  supplies  power s u p p l y  and  setup,  i s t o provide display  and  s i g n a l on an i n t e n s i t y  The t a s k c a n be synchronization  divided of  a  into setup  116  staircase the  ( g r e y s c a l e ) and b i n a r y t i m e  video  signal;  vertically scale, has  t h e slow  across the screen  and  the  f r a m e code o r v i d e o s i g n a l .  been i m p l e m e n t e d  former,  called  freguency, clock  scanning  high  the l a t t e r ,  freguency  operate fourty  on i n d i v i d u a l  signal  (frame  code)  with  o f the o s c i l l o s c o p e  trace  selection  The c i r c u i t r y printed  speed  logic,  called  low s p e e d  conductor  flat  and  operates  cable  grey  f o r each  area  boards.  The  w i t h a 1 MHz c l o c k  logic,  communicate  the  circuit  operates  which i s a s u b m u l t i p l e o f 68 Hz.  asynchronously  of  with  The two  a  boards  v i a connections  to a  buss.  HIGH SPEED LOGIC  The  basic  1 MHz c l o c k f r e q u e n c y  i n v e r t e r s a n d RC r e l a x a t i o n C7,  C8)  by  R33  ( F i g . A1.19), (pulse  temperature be  used  compensated  i s adjusted  The o s c i l l a t o r  t h e 1 MHz f r e q u e n c y  b i t 7  defines  When  a NOR  resistor-ladder  the  i s not  should  and  digital  using  by 128 t h r o u g h  ( F i g . A1.21). output  seven  not  stages  The g r e y  bits  1  i s low b i t s an  inverter  to  analogue  and t h e  frame  1, 2 and 3 each to  drive  converter  a  scale  through  t r a n s m i t t e r pulse r e p e t i t i o n  the grey s c a l e  b i t 4  gate  (4040)  derived  When b i t 4 i s h i g h b o t h disabled.  i s divided  counter  f r a m e code a r e  through  CMOS  (R32, R33, R73,  The f r e q u e n c y  rate adjust).  so t h a t  c l o c k freguency  of a binary r i p p l e  Output  A1.20).  circuitry  two  as a t i m i n g r e f e r e n c e .  The  and  oscillator  (Fig.  repetition  i s derived using  code  4.  rate. are  translate three b i t  (R34, R35, R36,  7  4051  enable  Frame C o d e  8 CHANNEL MULTIPLEXER  0 0 9  9 - 16  7K  4066  HIGH  parallel  ^  Frame Code  3 bit D/A resistor ladder  Trig  54S140  54121  4040  Trig  LINE  DRIVER  GENERATOR  COUNTER 1  DUAL  PULSE  BIT  Grey  Scale  J,  LOGIC  VIDEO IN  VIDEO MIXER  SPEED  serial  ;  MIXED VIDEO OUT  I  LOGIC  grey  DIAGRAM  scale  enable  31  frame code  enable  32  video  enable  37  FIG. A1.19  118  FIG. A1.20  R31  14  14  4040  4001  40 69  LI R35  R37  SR36  •vAAA—W\AA-  D7  R38  P39  R40 R41  54 S 140  16  14  14  5 4 1 21  C9  71  4051  4066  R42  4>n  5v  TRIG  TRIG  DISABLE  MIXED  VIDEO  VIDEO  N  r-  (N  n n n  HIGH  SPEED  LOGIC;  CIRCUIT  DIAGRAM °"'  " t  15v  MARK  S  imhz  iiiriJinjiJWLjmjLn^  FRAME CODE  FIG. A1.21  HIGH SPEED  LOGIC  TIMING  DIAGRAM 1  120  R37,  R38 and  switching scale  R39).  transistor  i s switched  bilateral  t h e grey  for  one  usecond bits  output  i s  the  multiplexed  video  line  a l s o go  Each s i g n a l  When b i t 4  i s  by a b i l a t e r a l  signal  As w i t h  switched  which comes f r o m  p a s s o n t o t h e mixed v i d e o c a n go h i g h  leading  cable  with  lines  by t h e  multiplexer  grey  scale,  (4066). onto  o n t o t h e mixed  When l i n e . 3 7 on t h e f l a t o n t o t h e mixed  video  s c a l e o r frame  line.  No  two  code  of the  simultaneously.  edges o f t h e grey  on t h e down t r a n s i t i o n  synchronized  l i n e s on an  being i n v e r t e d  the  i s a l s o switched  t h e grey  lines  high  except  the video a m p l i f i e r  31 o r 32 go h i g h  When l i n e s  the  a n a l o q u e CMOS s w i t c h  line.  start  This  as r e q u i r e d onto t h e  passes  both  select  high  the video s i g n a l  The  resulting  i s selected i n turn f o r  cable buss i s high  enabling  high  which a f t e r  phosphor.  code  a  phosphor.  i s  by an a n a l o g u e CMOS s w i t c h .  respectively  by  T h i s analogue m u l t i p l e x e r has  t o a low v o l t a g e ,  frame  grey  When b i t 4 i s h i q h a l l  i n f o r m a t i o n on e i g h t f l a t  v i a t h e edge c o n n e c t o r  line  line  at i t s highest value.  (4051).  the o s c i l l o s c o p e  video  card  speed  The b u f f e r e d video  also d r i v e the channel  1, 2 a n d 3.  blank  the  high  by t h e s e q u e n c e o f b i n a r y numbers d e t e r m i n e d  will  The  (4066).  by  s i g n a l s t h a t d r i v e t h e D/A c o n v e r t e r ,  multiplexer  forced  video  R40.  the o s c i l l o s c o p e  t h e frame code.  counter  mixed  being  t o t u r n incoming  (9-16) i n t o  buffered  t h e D/A c o n v e r t e r  polarity,  channel  i s  resistor  CMOS s w i t c h  blank  same t h r e e  been used  and  s c a l e output  opposite  eight  Q2  driving  l e v e l s i g n a l would The  output  a s r e q u i r e d o n t o t h e mixed  analoque  three signals in  The  of  s c a l e and f r a m e c o d e , the  the t r a n s m i t t e r t r i g g e r  counter pulse  b i t 4,  which are  which i s s t a r t e d  121  by  an up t r a n s i t i o n on c o u n t e r  the  transmitter  duty c y c l e  repetition  specification.  b i t 7 (Fig. period  The  AK22).  i s 128 u s e c o n d s ,  transmission  d e t e r m i n e d by t h e c y c l e t i m e o f a m o n o s t a b l e 15 V  bit  resistor  7  transition  reduced  E31 and Z e n e r d i o d e D7.  monostable v i b r a t o r capacitor of  i s  to  driver  (54S140).  adjustable driving  a  50il  transmitter  for  any o t h e r  The  line  heart  of  rate  0 V through  15 s e c o n d s .  The  The  silver  mica  The i n v e r t e d  are  output  inverting  line  drivers are  each  capable  of  One o u t p u t i s d e d i c a t e d i s available  t h e low s p e e d l o g i c a variable clock,  converter.  as  a  as  trigger  A1.23) i s a ramp  ten-bit  15 V o v e r one o f e i g h t  oscilloscope exposing  (Fig.  counter  The ramp o u t p u t v a r i e s a t a  The ramp p r o v i d e s  continuously  supplied  is  SPEED LOGIC  D/A  vertical  and  from the l i n e  They  The o t h e r  length  instrument.  nine-bit  modulated  R41  of a dual  pulse  ns.  pulse  edge t r i g g e r s a TTL  length.  a t TTL l e v e l s .  trigger.  generator comprising  from  output  f r o m 50 ns to 200  the  LOW  The  within i t s  a 0-5 V t r a n s i t i o n by  (54121) w i t h r e s i s t o r  the m u l t i v i b r a t o r d r i v e s the inputs  way  multivibrator.  The r i s i n g  C9 d e t e r m i n i n g t h e p u l s e  In t h i s  a means o f s c a n n i n g  trace  vertically  a frame o f  s c a n t h e ramp r e s e t s  binary  film.  across At  the  and  a  constant  multiples of an  intensity  the end  t o 0 V and w a i t s f o r an  screen, of  each  operator-  restart signal. basic  clock  rate i s determined  by r e s i s t o r s  B26,  R28,  f Q(  i  Q5  ~L  *| 16JJS n  n  Q6 Q7  1  GREY  SCALE FRAME  wYinnnnnnnnnr  CODE Tx  I" 50 nS  TRIG.  128 pS VIDEO  FIG. A1.22  k  k HIGH SPEED  LOGIC TIMING  DIAGRAM 2  rO  123  RESET <  17  r/vW-i 8  bit  RUN  frame  clock  counter clock 1-  15  8  -< 3 6  h / v W n  15 v to 5 v  18  BUFFER 2 x 4010A  Ramp  Grey  < 1 9  START XR 2 2 4 0  scale En  21-28  9 b i t D/A res istor ladder  6 8 H z clock & 8 bi t counter STOP  bits  bit 5  1- 9  •^30  Rs  <29  bit 10  READY  10 bit counter  clock  4040  LOW  SPEED  LOGIC  ;  LOGIC  DIAGRAM  FIG. A1.23  -<20  124  capacitor  C6  and  linear  integrated timer c i r c u i t an  eight-bit  flat  circuitry  (Fig.  binary counter  cable  buss  lines  in  A1.24).  w i t h open  21  to  the f r o n t  outputs  (4040)-  input to the counter  from  S1  clock  (flat  The  cable l i n e  fastest  approximately time  of about  half  the  8m, The  line C2  The e i g h t  Each  capacitor  a  ten  to a total  s u c c e s s i v e output  19) p a s s e s  monostable  k rising  through  vibrator (Fig.  diode  scan  counter  two NOR  connected  31).  comprising A1.25). .  to  bit  monostable counter  h i g h speed Just  is scan  exactly vertical 2m,  In  (flat  scale  i s connected  gates, the  B27 t h e 2240 t i m e r  into  flip-flops  which i s s e t  enable" l i n e  33).  has i t s cable  connected  The o u t p u t  t o t h e c l o c k o f an code  and  a r e each  (flat  has i t s o u t p u t  cable line  which s u p p l i e s t h e f r a m e  two NOB  The two f l i p - f l o p s  which i s r e s e t  line  vibrator  "grey  capacitor  addition  The f l i p - f l o p  the  The f l i p - f l o p  resistor  (4040).  gates.  to the "video enable" the  i s at  D2 and  mode, s e t s o r r e s e t s two o t h e r b i s t a b l e  line  R23.  edge on t h e " s t a r t "  counting  output  line  a r e 15s, 3 0 s , 1m,  pulse t r i g g e r s through  formed from  counter  vertical  twice the t o t a l  times a v a i l a b l e  C1 and r e s i s t o r B1  the  bit  by t h e 2240 t i m e r  "start"  resets  p a n e l s w i t c h S1  pull-up resistor  requirinq  Via  i s on t h e r e t u r n  generated  i s as f o l l o w s .  cable l i n e  set  scan  the  outputs.  32m.  scan c y c l e  (flat to  15 s e c o n d s .  16m and  with  This corresponds  previous frequency  scan time. 4m,  clock freguency  68Hz.  clock  20) a l o n g  triggerable  The 2240 t i m e r i n c l u d e s  s e l e c t s one o f t h e s e The  2240  collector  28,  to  the  information  of  eightto  the  logic multiplexer. after  the  start  pulse,  then, the frame'counter  i s  125  .<0 K 00<O •-  ——n  START (19) Q10 READY (29) CLOCK (20)  inniiririjijiji^  Q1  m ~ L j i _ r i _ r i J i J i j a j ~ L ^  Q2 Q3 Q4 GREY SCALE f ENABLE (31) FRAME CODE ENABLE (32) J  VIDEO ENABLE (33)  FIG. A1.25  1 L  LOW  SPEED  LOGIC  TIMING  DIAGRAM  1 CO  127  incremented  by one c o u n t ,  video  frame  and  proceeds  code  t o count  the grey are  up from  Q1  lamp B2.  When t h e s c a n c o u n t  bit  resets the f i r s t  d i s a b l e s t h e grey scan  count  second  bit  When  t e n causes  resistor glow  The  scan count  transistor  A1.27).  t h e low o r d e r  1  depowers  reaches  frame  (Fig.  reaches  ladder,  may  also  diode  D1 i n d e p e n d e n t  "run" o s c i l l a t o r  of the rest connect  code m u l t i p l e x e r v i a f l a t  TTL  levels  here  that  driver CMOS It  two 4010A b u f f e r on f l a t the  i s also  cable l i n e s  BCD  important  circuits  as used  here  design.  The 4010A  of  the  directly  circuits  9  1 t o 8.  that  frame  low  t o note here t h a t  by t h e f r o n t 36.  speed  16.  In  through  circuitry.  t o t h e h i g h speed to  only  level.  the counter  In  frame  addition,  i s provided at  (It i s important for the front  this circuit  t o seven-segment  t o note  p a n e l LED  was d e s i g n e d  decoders  were  the presence  forces the obsolescence of  with  the  uses  18 and  t h e frame c o u n t  are reguired  At t h e time  compatible  which  cable lines  cable l i n e s  TTL l e v e l s  circuits.  When  ( v i a d i o d e D5 a n d  be i n c r e m e n t e d  can increment  through  code.  Q1 t o s w i t c h on and " r e a d y " lamp B2 t o  way  outputs  T h i s change  hex'200' t h e h i g h l e v e l on  this  counter  A1.26).  t h e v i d e o and d i s a b l e s t h e  flat  The  indicator  t h e h i g h l e v e l on b i t s i x s e t s t h e  p a n e l s w i t c h S4 which c o n n e c t s a  "ready"  has r e t u r n e d t o a 0 V output  counter  counter  hex*010' t h e h i g h l e v e l on  The D/A r e s i s t o r  9 bits  and t h e  The 1 0 - b i t s c a n  t h e 2240 t i m e r t o s t o p c o u n t i n g  K29),  (Fig.  enabled  and e n a b l e s t h e frame  which e n a b l e s  the  and  is  The o u t p u t o f b i t 10 i s low  flip-flop  r e a c h e s hex'020  flip-flop  code.  scale  disabled.  hex'OOO'.  which t u r n s o f f t r a n s i s t o r  five  scale  no  available.  o f t h e 401 OA  the  presented  s e p a r a t e VDD and VCC a r e no l o n g e r b e i n g  START  Q 10  J | ~~|_  READY  J "  GREY SCALE  r ENABL  FRAME  CODE  ENABLE' VIDEO ENABLE  -| J  FIG. A1.26  LOW  SPEED  LOGIC  TIMING  DIAGRAM  START  —I  Q10  READY Q6 Q7 Q8 Q9  HI-  CLOCK GREY S C A L E ENABLE  JT  FRAME CODE ENABLE VIDEO  n n  Jl  ENABLE  FIG. A1.27  LOW SPEED  LOGIC TIMING DIAGRAM 3  130  made s i n c e  manufacturers  4010A  latch  to  when  found powered  that up  t h e r e was a t e n d e n c y in  specific  f o r the  manners.  No  alternates are available.) The  TTL l e v e l  frame c o u n t  into  seven-segment  drive  t h r e e s e v e n - s e g m e n t LED d i s p l a y s  the  operator  operator high  to  may a l s o  level  octal  i s decoded  preset reset  the. front  by t h r e e 9317B c i r c u i t s .  and  monitor  t h e frame count  s i g n a l onto f l a t  at  cable line  (Fig. the  w i t h S4 w h i c h 17.  The 9317B's  A 1.28)  frame  panel  allowing  count.  The  connects a  FIG. A1.28 •  in  d isable  1  s i  POWER FRONT  R  T  T  M  V  PANEL  RECEIVER  ;  CONNECTION  DIAGRAM  FIG. A1.29  133  Table  DL1  A4: R e c e i v e r R.F.  Diode L i m i t e r  MD-30T30  Module  Components  #001  Micro-^Dynamics i n c . Flat  l e a k a g e 50 mW  Recovery Insertion  M1  time  max.  S p i k e l e a k a g e 0.1 e r g max.  100 n s max.  l o s s 0.5 dB  max.  Double Balanced Mixer  MA-1  M i n i - C i r c u i t s Laboratory Insertion LO  BP1  loss  level  +10 dB  Bandpass  Filter  9.0 - 10.0 dB  3B120-120/40-op/o #5267-1  K & L Microwave I n c .  A1  P a s s band  99 MHz t o 141  Insertion  l o s s 0.4 dB  Logarithmic IF Amplifier  MHz  I C L T 1 2 0 4 0 #7-511-1  RflG E l e c t r o n i c s L a b o r a t o r y I n c . Dynamic r a n g e -70 dBm P a s s band  t o +10  dBm  99 MHz t o 140 MHz  R i s e t i m e 20ns max. Log.  linearity  Output  range  ±1 dB o v e r 70 dB  +0.4 V t o +2.8 V  Power r e q u i r e d  ±12 V S 130 mA  max.  134  Table  A5: R e c e i v e r  Components: R e q u i r e d  7805  +5 VDC V o l t a g e r e g u l a t o r  78M12  +12 VDC V o l t a g e r e g u l a t o r  79M12  -12 VDC V o l t a g e r e g u l a t o r  3400A  Operational amplifier,  4001  CMOS quad NOR g a t e (x5)  4040  CMOS 12 b i t c o u n t e r (x3)  4010A  level  4051  CMOS a n a l o g u e m u l t i p l e x e r  4066  CMOS quad b i l a t e r a l  4069  CMOS hex i n v e r t e r  2240  NMOS t i m e r - c o u n t e r  54121  TTL  monostable  54S140  TTL  dual 5-input  9317B  TTL  seven  MAN3610  LED s e v e n  Required  Power Module  shifting  Burr  hex b u f f e r  Integrated  Circuits  Brown  ( o b s o l e t e ) (x2)  analoque  switch  vibrator NAND l i n e  segment from  driver  BCD d e c o d e r - d r i v e r (x3)  segment d i s p l a y ,  0.300", Monsanto (x3)  Model 528, 28 V t o ± 1 5 V DC-DC c o n v e r t e r , B u r r  Brown.  135  Table  A6: B e e e i v e r  D i s c r e t e Components P a r t s  List  Q1 2N4238  D1 1N914  Q2 2N3014  D2 1N914  Q3 2N4238  D3 1N914  Q4 2N4238  D4 1N914  C1 17 u f d , 16 V  D5 1N914  C2 17 u f d , 16 V  D6 1N914  C3 3.3 u f d  D7 5 V Z e n e r ,  1w, DO-7  C4 1000 p f d  D8 1A s i l i c o n  rectifier  C5 3.3 u f d  D9  1A s i l i c o n  rectifier  C6 3.3 u f d  D10  1A s i l i c o n  rectifier  C7 470 p f d  Odd  1A s i l i c o n  rectifier  C8 470 p f d  B1 27K  C9 90 p f s i l v e r m i c a  B2 27K 0.25w, 5%  C10 47 u f d , 16 V  B3 33K  C11  E4  1000 p f d  100K  0.25w, 5%  0.25w, 5% 0.25m, 5%  C12 1000 p f d  B5 100K 0.25w, 0.4%  C13 22 u f d , 35 V  B6 50K  C14 22 u f d  B7  C15 41 u f d , 16 V  E8 50K 0.25w, 0. 8%  100K  0.25w, 0.4% 0.25w, 0.8%  15 u f d , 35 V  B9 100K 0.25w, 1%  C17 1 u f d , 250 V  B10I 50K 0.25w, 1%  C18 22 u f d , 16 V  E11  C16  100K 0.25w, 1%  TABLE &6, CONT. B12 50K 0.25w, 1% B13  100K 0.25w, 5%  B14 50K 0.25w, 5% B15  100K 0.25w, 5%  E16 50K 0.25w, 5%  B36  10K 0.25w, 5%  B37  10K 0.25w, 5%  B38 4700 0.25w, 5% B39 4700 0.25w  r  5%  B40 470 0.25w, 5%  B17  100K 0.25w, 5%  B41 2K t e n t u r n  B18  100K 0.25w, 5%  B42 4700 0.25w, 5%  B19 50K 0.25w, 0.2%  B43 5600 0.25w, 20%  B20  100K 0.25w, 0.2%  B44 5600 0.25w, 20%  B21  100K 0.25w, 0.1%  B45 220K 0.25w, 5% 220k 0.25w, 5%  B22 50K 0.25w, 0.1%  B46  B23 10K 0.25w, 5%  B47 0.25w, 5%  B24 1K 0.25w, 5%  B48  10K t e n t u r n  B25 18K 0.25w, 5%  B49  10K t e n t u r n  R50  12K 0.25w, 5%  B27 47K 0.25w, 5%  B51  1K 0.25w  B28 3900 0.25w, 5%  B52  180 0.25w, 5%  B29 47K 0.25w  B53  180 0.25w, 5%  R54  180 0.25w, 5%  B26  10K t e n t u r n  5%  #  5%  B30  1M 0.25w  B31  270 0.25w, 5%  B55  180 0.25w, 5%  B32  1800 0.25w, 5% (x2)  B56  180 0.25w, 5%  B33 1K t e n t u r n  B57  180 0.25w, 5%  B34 10K 0.2 5w, 5%  B58  180 0.25w, 5%  10K 0.25w, 5%  B59  180 0.25w, 5%  B35  #  5%  #  137  TABLE A6, CONT. B60 180 0.25w, 5%  E71  180 0.25w, 5% 180 0.25w, 5%  E61  180 0.25v, 5%  E72  E62  180 0.25w, 5%  L1  E63  180 0.25w, 5%  S1 8 p o s i t i o n  rotary,  R64  180 0.25w, 5%  S2 MTA-206SA,  Alco  E65  180 0.25w, 5%  S3 MTA-206S,  E66  180 0.25w, 5%  S4 MTA-206S, A l c o  E67  180 0.25w, 5%  S5 p u s h - o n , p u s h - o f f ,  E68  180 0.25w, 5%  Grayhill  E69  180 0.25w, 5%  S6 MTA-206TA, A l c o  E70  180 0.25w, 5%  B1 28 V t u n g s t e n  B2 ;28 V t u n g s t e n  panel  lamp  106S, Hammond Grayhill  Alco  panel  SPST,  lamp  138  A 1.4 THE SWITCHING REGULATOR The  following  POWER SUPPLY  d e s c r i p t i o n s are excerpted  i n part  ARRL R a d i o Amateur's Handbook ( 1 9 7 5 ) , and from Application  Note  Switching desired the  pass  regulator, referring and  current  The as  t o Figure the  stabilize.  of  transistor  known  that  the  E,  inductor  because  RI).  When  collapse  equal t o that  large  has  in  the load  only  of  the  switching  may be u n d e r s t o o d by  the  switch  operation RL,  i s  i s  long zero,  the switch higher  and  completely,  o f the source switch  lines  i s opened, t h e  than  the  of  voltage  (minus t h e s m a l l i s  closed  the  flux  then  effect of  drop  voltage  be a p p l i e d  the  DC i n p u t  produce a discharging in  DC  voltage. output  In  A capacitor voltage.  when t h e s w i t c h  s e r i e s with t h e l o a d a practical  across  RL w h i c h a r e h i g h e r  keep  i s closed,  the  capacitor  than RL t o from  a d i o d e c a n be c o n n e c t e d  and i t s p a r a l l e l - c o n n e c t e d  switching-regulator  the  rapidly,  may be c o n n e c t e d a c r o s s To  be  across  opened,  By o p e n i n g a n d c l o s i n g t h e s w i t c h  may  the  RL w i l l  process i s repeated. pulses  source  about  across voltage  and  the  resistance  o f a s e r i e s - a i d i n g or " f l y b a c k " magnetic  closed  enough t o  by R I , t h e i n t e r n a l  goes t o a v a l u e  in  variations i n input or  type,  been  across  the  Each time the  i t i s necessary or  operation  At t h e i n s t a n t t h a t  the load  inductor.  when  Assume t h a t  through L i s l i m i t e d  voltage,  Delco E l e c t r o n i c s  which would o t h e r w i s e o c c u r  flyback  A1.30a.  The v o l t a g e  across  used  with  basic  the  circuit  the inductor.  voltage  are  power l o s s e s  voltages.  the  (1971).  regulators  t o minimize  series  output  #4 9,  from  circuit  capacitor.  the switching i s  139  L  RI AA/Sr  SWITCH  IDEAL VOLTAGE SOURCE  (A)  +  o  DC INPUT  MULTI-  DRIVER  VIBRATOR  (B) FIG.A1.30  SWITCHING REGULATOR BLOCK  DIAGRAM  RL  140  performed  by  transistor circuit  may  used  circuit, The  a transistor,  voltage  accordingly. from  the  width.  i n the  triggers  the  The  any  in  Figure  number o f  sections  block  d i a g r a m form  of o p e r a t i o n . pulse  The  A 1.30b.  circuits.  make  monostable  c o n t r o l s the  up  the  and  sensor  d r i v e r r e c e i v e s the  power t r a n s i s t o r  The In  the  driving  i n f i g u r e Al.30b.  multivibrator  and  sensor  the  width of  measures  the  multivibrator  monostable m u l t i v i b r a t o r combines the  oscillator  The  by  the  freguency and  shown  A1.31) f o u r  shown  oscillator  output  driven  (Fig.  as  determines  the  be  as  to produce the  signals  correct  m u l t i v i b r a t o r output  and  pulse drives  Q1.  A1.4.1 PRACTICAL CONSIDERATIONS The  voltage  step-up  capability  discussed  briefly.  inductor,  e n e r g y i s an i m p o r t a n t  the  transistor  energy  i s added  transistor supply  the  t o the  load the  off.  and  through operation  the  the and  inductor  is  i s over a small curve. and  The  has  been  value  of  the  During  the  time  the  s t o r e s energy.  d e l i v e r e d t o the  total  e n e r g y must  output  be  voltage. on  load  when  the  enough ' t o  As  longer  This  the  in  load  order  is to  inductor.  value  inductor  mu,  choosing  inductor  consideration.  maintain  d u t y c y c l e , and  discharging a low  The  in  t r a n s i s t o r must r e m a i n  required  operation,  on,  supply  more e n e r g y i n t h e The  has  i s turned  is, turned  increased, store  However,  of the  of inductance load. a  A  linear  change  frequency in  d e s i r a b l e c o n d i t i o n and  segment o f  powdered i r o n  therefore  d e p e n d s on  a  the  inductor's  core  large  used  current indicates  charging  f o r the  inductance  of  and  inductor  change  is  FIG. A1.31  SWITCHING  REGULATOR  CIRCUIT DIAGRAM  142  unlikely  with i n c r e a s e d  Efficiency and  saturation  through  the The  recovery  time  and  i s considerably  diode low  (D1)  used because  has  have  drop.  through the t r a n s i s t o r  The  greater  must  forward  used i n t h e c i r c u i t  Output  depends m a i n l y upon t h e  l o s s e s o f t h e power t r a n s i s t o r .  flyback  current spike  is  of the c i r c u i t  transistor  current.  diode  current.  peak  fast will  voltage variations  input  reverse a  large  i f the diode i s slow.  The  a f o r w a r d d r o p o f 1.4  o f i t s t r r o f 0.1  current  than the  a  There  switching  be  V max.,  but  us.  resulting  temperature  are  caused  by  two  temperature  coefficient  of  temperature  coefficient  of  the  the  circuit  from changes  major  the Zener  in  factors:  d i o d e s , and  emitter  ambient positive  the n e g a t i v e  diodes  of  the  a t low  power  transistors. The levels. are  efficiency T h i s i s due  not  to the f a c t  proportional  o c c u r s at about Regulation Whenever  of  80%  the i n p u t  voltage tracks  the  voltages i s the drop  off  the l o s s e s of the  t o t h e o u t p u t power.  of f u l l  over the  that  drops  Maximum  circuit  efficiency  power.  power o u t p u t r a n g e i s l e s s  v o l t a g e i n c r e a s e s above 28 input.  The  difference  i n the f l y b a c k  than  0.6%.  the  output  volts, between  the  two  diode.  A1.4.2 CIRCUIT DETAILS The large 10A-  and  principal occupy  Darlington  c a p a c i t o r s each  components, L 1 , Q1,  most o f t h e s p a c e transistor one  in  a  D1  and  C1  are  i n the r e g u l a t o r . TO-3  capable of s u s t a i n i n g  case. full  C1 load,  physically Q1  is  a  includes  two  so t h a t  the  143  regulator  can remain s e r v i c e a b l e s h o u l d  one  of  the  capacitors  fail. All printed R15,  the t r a n s i s t o r circuit  C6  and  operating  and  at about  with C4,  form  C5.  is  conducting.  Q2. the off  If  o f f by  duty  oscillator monostable  the  vibrator.  output  a reference Q2  R8,  Pulse  t h e output  Q4 t u r n s  width  voltage  sensing  voltage.  pulse  voltage i s s u f f i c i e n t l y  on, d r i v i n g  R12  t h e base o f Q2.  i s conducting  negative  R11,  and Q5 i s n o n -  from  Q6, t h r o u g h  through  C4.  t i m e o f R8 and C4 d e t e r m i n e t h e maximum d u t y  o f Q4 a n d r e d u c i n g "on"  state  a  the  current into  t a p o f P1 a p p r o a c h e s t h e r e f e r e n c e and  to  When Q5 i s t r i g g e r e d on by a p u l s e  Q2 i s t u r n e d  relaxation  coupled  monostable  by i n j e c t i n g  quiescent  which i n c l u d e s R13, R14,  components R4, R6,  R9, D2 and C3 form  the  on t h e  Q2, a n d Q5 a r e t h e two t r a n s i s t o r s ,  R2, R7, P1, C2, Q3 a n d Q4 form  In  h a s been p l a c e d  unijunction transistor  It  the  i s achieved  circuitry.  C5  9 KHz.  through  which  circuitry  The o s c i l l a t o r ,  b i a s i n g and t i m i n g  modulation R1,  board.  Q6, i s a n o r m a l  multivibrator along  driving  level  high of  The  cycle of  t h e v o l t a g e on D2.  Q3  turns  t h e base o f Q2 f r o m t h e c o l l e c t o r  the " o f f " duty  c y c l e o f Q2.  T h i s reduces the  c y c l e o f Q1 w h i c h c o m p l e t e s t h e f e e d b a c k  loop.  144  Table  Q1 DTS  A7: S w i t c h i n g  Regulator  Parts  R3 220 0.5w, 5%  1020, D e l c o  1500  0.5w, 5%  Q2 2N930  R4  Q3 2N3251  R5 6800 0.5w, 5%  03  26  1500  0. 5w, 5%  Q5 2N930  R7 1800  0.5w, 5%  Q6 2N1671B  R8  C1 22,000 u f d , 35 V (x2)  R9 680 0.5w, 5%  C2 50 u f d , 15 V, 10%  R10 62K 0.5w, 5%  C3 220 u f d , 25 V, 1016  R11  1800  0.5w, 5%  C4 6 8 0 p f d , 10%  R12 1500  0.5w, 5%  C5 0.0033 u f d , 10%  R13 680 0.5w, 5%  C6 0.033 u f d , 10%  R14  D1  R15 47K 0.5w, 5%  2N3251  1N3889  D2 18 V, 1 watt R1  1200  0.5w, 5%  R2  1800  0.5w, 5%  List  150K 0.5w, 5%  120 0.5w, 5%  P1 500 Ohm,  Zener  L1  1.1 mH,  10 T u r n 16AWG on  Armaco FBC c o r e  Miscellaneous: 1 - Wafer s w i t c h , 4 p o s i t i o n , 1 - T u n g s t e n p a n e l lamp, 1 - Panel  single  pole  28 V  m e t e r , 50 VDC, KM-48, H i o k i ,  1 - HKP Buss f u s e h o l d e r , w i t h  with  7.5 amp f u s e  diode  145  A1.5 THE COENEB EEFLECTOB ANTENNA The a  two  University element,  reflector  performance corner  90°  type  construction  and with  is  reflector,  the  dipole  both  a  high  sophistication.  in gain  The  90°  i n forward  gain  with the  and a l s o r e d u c e s t h e  90°  sidelobe  o f a i r p a t h r e f l e c t i o n s from  o f the U n i v e r s i t y  10 dB p r o v i d e d  3 dB f r o m  At 840 MHz,  convenient provide  uses  o f B. C.  by t h e c o r n e r  the double d r i v e n  antenna reflector  e l e m e n t and 2 dB by  radiators.  A1.5.1 The  are  little  echo sounder  antenna.  and  i n consideration  Forward gain  A1.32),  reflector  application,  15 dB o v e r i s o t r o p i c ,  (Fig.  radio  compares': f a v o u r a b l y  important walls.  Columbia  antennae  relatively  "ideal" parabolic  valley  corner  aperture  reflector  level,  of British  two  radiators,  DESIGN DETAILS driven  are  elements,  located  electric  approximately  half-wave  dipole  (150 mm)  from t h e  0.4X  apex o f t h e c o r n e r .  Their  centre-to-centre  (536  At t h e s e  points  t h e nominal r a d i a t i o n r e s i s t a n c e f o r  each d i p o l e  i s 100i2  (see f i g u r e A 1 . 3 3 ) .  separately  by  form is  mm) .  a 100&  a "T" j u n c t i o n an  exact  coaxial cable.  with  multiple  centres.  The 50Q. c o a x i a l c a b l e  from(to)  the radar  driven  in  direction,  phase and  transceiver. with  with  Each  is  dipole  at a  1.5 X  i s fed  The 100 D. c o a x i a l  a 50 £l c o a x i a l c a b l e  of a h a l f  spacing  cables  point  which  wavelength from t h e d i p o l e i s the  power  In this  corresponding  an e n h a n c e d n u l l  feed  feed  connection  manner t h e d i p o l e s a r e  gain  in  the  forward  i n the E - plane  90° s i d e  U6  GO  < O Q CC <  or o LL 1  "0  CORNER  2  REFLECTOR-DIP0LE SPACING AFTER  JASIK.  1.0  2.0  CORNER REFLECTOR-DIPOLE SPACING AFTER  JASIK.  (WAVELENGTHS)  1961  FIG.A1.32 CORNER R E F L E C T O R  0  3  G A I N vs SPACING  3.0  (WAVELENGTHS)  1961  FIG.A1.33 C O R N E R R E F L E C T O R IMPEDANCE vs SPACING  147  lobe d i r e c t i o n . The  d i p o l e e l e m e n t s were d e s i g n e d and c o n s t r u c t e d  University  of  British  Badio L a b o r a t o r i e s a  broadband  Construction The  eight in  dipole  element,  echo s o u n d e r by S i n c l a i r  Canada. balun  Each d i p o l e and  a  PVC  (Fig.  i s fabricated  A 1.34).  of  Each s i d e o f t h e r e f l e c t o r  (9.5 mm) t u b e s s u s p e n d e d  The r e f l e c t o r s and d i p o l e  galvanized  reflectors.  steel  driven of  brackets,  has  a t 1.75" (44 mm)  centre  been  t h e radomes.  The  approximately  absence  placed  elements  precisely i n place  a  half  parasitic  feed field  e f f e c t of the p a r a s i t i c of  a  parasite,  resulting  reducing  in  the  fields  BF  way between t h e two  the  two  i s as f o l l o w s .  driven  currents on  tube  In the  around each  delay  power r e t u r n i n g  parasite  extension  t h a n 0.5X .  fields  cycles  The p a r a s i t e  the cross-over  effect of BF  1.5  parasitic  c o n s i s t s o f an a l u m i n i u m  element  static  with  a n d a p o o r e r VSWB.  minimal.  by  o f t h e e x t r a element i s  20 mm d i a m e t e r a n d 10% l o n g e r  element  The  element  third  by a f i b r e g l a s s  The p r i n c i p a l f u n c t i o n  element i n d u c e c u r r e n t s driven  place  supports are bolted to  i m p r o v e t h e VSWB o f t h e a n t e n n a by i s o l a t i n g  The  in  centres  which d e t e r m i n e t h e a n g l e o f t h e  t o t h e two d r i v e n  e l e m e n t s , and i s h e l d  dipoles.  comprises  A l l h a r d w a r e i s t y p e AN.  In a d d i t i o n element  radome.  T6 a l u m i n i u m t u b i n g a n d  0.75" x 1.50" (19 mm x 38 mm) c h a n n e l s and h e l d  two  comprises  d e t a i l s are proprietary.  0.375"  rivets.  to  L t d . , Burnaby,  reflector  channeling  Columbia r a d i o  f o rthe  i n  driven  the  other  i n t o the antenna  i n t e r f e r e s with the s t a t i c considerably. t h e , antenna  pattern  a t t h e p a r a s i t e a r e 0.75 c y c l e s  i s  behind i n  U8  FI6A1.34  THE CORNER REFLECTOR ANTENNA  U  61cm  A  *\  '  n  r V i- H rh  n  f  1  )  = l l = =  53.6cm  c  •  122 cm  SECTION A-A  )  1  A  149  phase t h o s e being parasite being  must  net  1961,  0.5X  r e r a d i a t i o n be  effect i s that  being  parasitic  by  the  dipoles.  parasitic advanced  being  i n the  considerably  G  and  respectively, reradiating relative  to  patterns  are  the  pattern  H for  are an  power w i t h power probably  The  E  t  the  forward  that  (cf. p.  Jasik,  5-6)..  parasitic  any  The  element  d i r e c t i o n , with  Assuming  the  power  reasonable  in additional  l e s s than  1  Figure  plane  dB.  patterns and  with  H a  based  -  from the real  on  this  patterns  parasitic  element  driven  and  10%  elements.  antenna  same a n t e n n a  A1.35  plane  phase l a g d e l a y  c l o s e s t to the  c a l c u l a t e d f o r the  elongation  results  cycles  radiating  further  that  however,  antenna 0.15  slight  antennae,  The  ahead o f  element r e g u i r e s  from  shows a s e r i e s o f t h e o r e t i c a l a n t e n n a e model.  centres.  cycles  still  driven. d i p o l e s .  parameters  dipole  power 0.75  power r e r a d i a t e d  element  gain  driven  elements i n Yagi  constructively  radiated  forward  driven  ) of the  reflector  interferes  at t h e  reradiate  from the  to  phase o f t h e H.,  then  radiated  (relative  radiated  with  pattern. no  power These A is  parasitic  element.  O v e r l e a f : F i g u r e A1.35. Theoretical patterns f o r various corner r e f l e c t o r antennae. E a c h p a t t e r n has assumed t h e p r e s e n c e o f an i d e a l 90° c o r n e r a t 0.4 X s p a c i n g , w i t h two d r i v e n d i p o l e s . Only the parasitic dipole parameters have been v a r i e d . Pattern A shows t h e e s t i m a t e d pattern with no parasite present. The number above each of the o t h e r p a t t e r n s r e p r e s e n t f i r s t the assumed r a d i a t e d power o f the p a r a s i t e r e l a t i v e to the driven d i p o l e s , s e c o n d the phase l a g o f t h e p a r a s i t e r a d i a t i o n r e l a t i v e to the driven dipole radiation. The p a t t e r n s p l o t r e l a t i v e power v e r s u s a n g l e .  150  FIGURE A1.35  151  A1.5.2 CALIBRATION: VSWR Voltage Radio (840  standing  Laboratories  wave r a t i o s have been p r o v i d e d Ltd.  MHz) and a p p r o x i m a t e l y The f o r w a r d  vertical  gain  incidence  of  P  and  R  P  antenna a l t i t u d e  T  Figure was  flown  clear  the  antenna  e  -  J  M  frequency  (±20 MHz).  been  measured  at  the relation  L  and L i s t h e s y s t e m l o s s e s i n t o be a p e r f e c t  power, dB.  r i s the  The  water  reflector.  recorded  a t 165 m above t h e s u r f a c e  data  0  has  a r e r e c e i v e d and t r a n s m i t t e d  A1.36 i s an echogram  specular  Pertinent  1.4 a t t h e band edqes  _ y ^  s u r f a c e h a s been assumed  by S i n c l a i r  VSWR i s 1.14 a t t h e c e n t r e  o v e r a l a k e by u s i n g  %  where  AND FORWARD GAIN  over Kluane Lake.  (1.1 us d e l a y )  reflection  with  received  power  a r e . i n Table  A8.  I t follows  and shows  It a  o f +2 dBm ± 2 dB.  that  2G - (14 + 81) = -64 dB ± 2 dB o r G = 15.5 dB ± 1 dB.  152  Figure  A1.36.  An  A - s c o p e echogram o v e r K l u a n e  The f i r s t p u l s e i s the t r a n s m i t t e d p u l s e . i s a +2 dBm r e f l e c t i o n f r o m t h e l a k e s u r f a c e . is a multiple r e f l e c t i o n o f f the a i r c r a f t . 1.1 us i n d i c a t i n g an a i r c r a f t c l e a r a n c e o f 165  lake  The s e c o n d p u l s e The third pulse The e c h o d e l a y i s m.  153  T a b l e ft8: F o r w a r d G a i n  Transmitted Beceived System  power  Measurement  (4 KW)  Power  66  Data  dBm  2 dBm  ±2 dB  Losses: C i r c u l a t o r I n s e r t i o n Loss I.F. F i l t e r I n s e r t i o n Loss Diode L i m i t e r I n s e r t i o n Loss Mixer Conversion Loss Cable Losses VSWB L o s s e s  0.50 dB 0.4 dB 0.1 dB 10 dB 2.7 dB <1 dB  Total  14 dB  Geometric  Losses:  loss  factor  -81 dB  154  APPENDIX  2: TRAPRIDGE  GLACIER AND  HAZARD  GLACIER  FLIGHT  LINE  MAPS Figure lines  A2.1  shows  the p o s i t i o n s  on t h e T r a p r i d g e G l a c i e r .  flights  Figure  recorded A2.2  along  shows  on t h e H a z a r d G l a c i e r .  along  approximately  glacier The  by  Depth  data  lines.  depth  80% o f t h e s e  flight  of three data lines.  of a l l controlled  flight  were s u c c e s s f u l l y The h i g h e r  f o r r e c o r d e r dead t i m e  was  taken  density  t o occur  was  a tthe  boundaries. three  triangles  drill  sites  work  (Napoleoni  location  Ice  approximately  90% o f t h e s e  arranging  1976.  the positions  lines  achieved  The map i s a c o m p o s i t e  made on A u g u s t 28 and 2 9 ,  successfully  of a l l c o n t r o l l e d  occupied  on  Figure  A2.2  represent  d u r i n g t h e s u r f a c e d based  and C l a r k e , 1 9 7 8 ) .  of the frontispiece  three  part of the f i e l d  The a s t e r i s k  photograph.  the  represents the  157  APPENDIX - 3:  DIFFRACTION FROM A LINEAR  To  i f i t i s p o s s i b l e to  decide  spherical field  predetermined  Three assumptions are negligible,  i.e.,  we  1973),  antennae  are  the  only  that  same  model and  scatterer  the  receiver  solve  f o r the  transmitter  location,  and  that  of  diffracted antennae.  polarization effects  to  the  a linear  are  s c a l a r wave  and the  receiver scattering  is horizontal.  The  model used h e r e  be  modelled  The  width  as  of  dimension' neglected  a  the  of  a  assumes t h a t  flat,  ribbon  be  zone,  "edge" d i f f r a c t i o n term.  diameter  relative  to  parallel  t o the  line  such s m a l l  line  does  not  (Huynen,  imply  preferentially  polarize  Objects shaped  like  very  scatters  scatterers  but  that  dipoles  in  radiation  will  cm  exist  scattering  will  always 20  in  objects  radiation  the  large  the  (small  polarized wavelength glaciers. which  won't  a l s o have t h i s  that  to  scatterer  With our not  to  relative  line  may  reflectivity.  comparison  small  thin  backscattered  small  scatterer  sufficiently  1978).  likely  linear with u n i t  small  terms are  (A  X)  the  narrow r i b b o n  must  Fresnel  diffracted  This  transmitter  need  (Berry, at  to  convenient: that  solution  total  detect  waves i t becomes n e c e s s a r y  for  object  RIBBON SCATTERER  do  exist.  property.)  A3. 1 COORDINATE SYSTEMS  Three  systems  are  useful  rectilinear  system, r e f e r e n c e d  (X'»Xa#Xj)  on  object  below  the  the  object  antennae,  to  "(Figi Xz  is  f o r the the  following  antennae  locates  A3.'!)'."• X i ' i s * t h e the  analysis.  distance  to  a  depth the  A  point of  the  point  w  . A3.1  SCHEMATIC  SCATTERER  OF  MODEL  RIBBON  159  parallel point  t o the E-axis  normal t o t h e E-axis  distances  a  off-vertical  polar  angle,  antenna E - a x i s , A third  system  object.  object.  the  antenna.  system r e l a t i v e  <**<j>  Assume  to the  that a l l  will  on  the  scattering  a h o r i z o n t a l vector  D  normal  to the  D relative  L e t t h e e n d p o i n t o f IT d e f i n e t h e o r i g i n  L-axis  along  the  object,  through  zero.  I t follows  with  to the  o f f ^ v e r t i c a l a n g l e t o p o i n t s on  L e t «. be t h e a z i m u t h o f t h e v e c t o r  antenna E - a x i s .  8 the  distance.  also l o c a t e a point  be t h e minimum  This defines  t o t h e antenna with  (see below) t h e a z i m u t h r e l a t i v e  and R t h e r a d i a l  L e t /3  object.  of  i s the distance  a r e measured i n w a v e l e n g t h s .  Define  the  o f an a n t e n n a ,  L  increasing  as  to the of  an  increases  that  D = JTDI = X . tan/3  It  follows  X2  = - L s i n c * + Dcosoc  A3=  Lcosc* + Dsinoc .  that  X.  = (--J=- sin a D 1  + cos a } tan £ J  = { -L- cos a + sin a } tan /9  and  (A3..1)  (A3.2)  160  t a n  20  **  s  +  x  »  =  / J L _ + l} tan*/3  X?  D  2  (A3.3)  + tan /3  L  2  X,  2  and  that  (A3.4)  tan  By  introducing  +  =  =  D  ~T7~  a parameter  c  o  t  X  #  = L/Xi these  0= 0 (£ ,£) = arctanU + ton /3) 2  4> =  may  Longhurst,  1957, p.  INTEGRAL  a n a l y s i s i s modelled a f t e r  electromotive  scatterer  is  (A3.5)  C  following  received  l/2  ,/S) = aretan(£ ot/3)  A3.2 THE KIBCHHOFF  The  2  reduce t o  be  reasonable during  force  estimated  (EWF) with  echo  sounding.  a  (1972).  The  linear  ribbon  K i r c h h o f f ' s formula  (see eg.  192, eq^n 10-15) .  from  Berry  Assuming  Xi »  \  , which  161  d  y  =  6  F'(t-2R/c)cosg  1  2*cR where d £ and  I  (See  i s  eg.  eg'n  i s the received a  A-1).  1957, p.  Integrating  *  6 )  2  c o n t r i b u t i o n from  guasisinosoidal  Longhurst,  ( A 3  area  element  wavefunction of f i n i t e 193,  eg'n  over t h e h o r i z o n t a l  10-16;  d£ ,  duration.  Berry,  1972,  plane,  F'(t - 2 R / c ) R  CTT C  3  2tC  • «  F'(t -2R/c) RX.  R  2  F'(t - 2R/c) 2  where  S= ( X  S=(X ,X- ) z  i  horizontal  2 + 2  «  J  X^ )  from  z  l  J  /  follows  that  i s  the  length point  of the h o r i z o n t a l  to a specified  point  vector i n the  Since  S  it  2  the suiantenna  plane.  ,13.7)  1  2  = S-5 = 5-VsR  (A3.8)  162  (A3. 9)  By  vector  471, eg'n  identity  ( s e e , e.g.  P a n o f s k y and  Phillips,  p.  7)  V*-(«// A) = AvV^  ^  +  F(t-2R/cJ?  ^VA  S-7 F(t-2R/c ) fi  =  R Xi  f  R Xi  2  z  + F(t-2R/c)Vs[^.J By t h e d i v e r g e n c e A3.10  1962,  vanishes  theorem (see,  the i n t e g r a l  e.g.  over  Stratton,  the  left  p.  429,  1941,  (A3.10)  side eg'n  of 34).  Thus  / / F ( t - 2 R / c ) V y y dT s  - _ ff S VsF(t-2R/c) JJ R Xi  d Z  2  2  .  Thus  with  A3.9  'C  ff  F'(t  -ZR/C)  R X. 2  f n n  -S-VsRdS  (A3.11)  163  j _ ; /  +  Evaluating  the divergence  F  (  term  d_ r  .  t  2  R  /  c  , ^ . i ^  i n t h e second  d  r  (A3.12)  integral  X2  a x Lx,(x, +x| +x|) z  2  ax lx,(x. +x +x )J 2  3  2  2  3  2  2X,(X, +X +X, ) - 2 X . X X, (X, +X +X ) 2  2  2  2X.  2  2  2  2  2  2  2  3  2  (X/ + X +X ) 2  Thus w i t h  3  2  - 2X.X  3  2  3  X. (X. +X +X ) 2  2  g  2  2  3  2  2  2  2X, R 4  (A3.13)  A3. 12  F'(t-2R/c) RX,  ^ / / F O - a R / o ^ j d j ;  (A3. 14)  Since F i s g u a s i - s i n o s o i d a l  with predominant frequency,  s a y to , 0  164  F'  As  assumed  A << X i  = «o  R  }  F  0  (A3. 15)  hence  I R  Thus t h e s e c o n d t e r m  The  effects  of  transmitter  the  antenna  pattern  constant  linear  XiH§  (A3.16)  weight  rrF'(t-2R/c)  scatterer unit  *(?)as — -  dw  runs  z  f  i s  modelled  then  ( F'(t  assumptions are r e q u i r e d sufficiently  narrow t h a t  as  r e f l e c t i v i t y on  /  across  integrand.  For  „  - 2R/C P  the  the  a narrow r i b b o n o f ribbon  and  zero  dZ. c a n be r e p l a c e d by dL o r by  and t h e i n t e g r a l becomes a l i n e  F  the  then  <  o f f the ribbon  -I  where  patterns  G-j.(@> H  width with  reflectivity  C  K  i n t h e i n t e g r a l c a n be n e g l e c t e d , and  -I  If  <  t  width,  integral  )  '  G_ dL dw  W,  of  the  (A3.19)  ribbon.  Two  forthis  expression;  t h a t the ribbon i s  across  i t s width  the  inteqrand  is  165  effectively at the  constant,  ribbon  reguires within  that  one  ribbon,  _  edge  can  the  width  Fresnel  P  w  {  X i  .  +  [  x  that e f f e c t s be  c a u s e d by t h e d i s c o n t i n u i t y  ignored.  The  of the r i b b o n  zone.  The  , _  phase  +  [  X  j  -  first  assumption  be, a t any p o i n t , difference  ^ i i ± ^ >  well  across  f  the  f  = {x +X +X +^+[x wcos(* + a) + X wsin(4>+a)]} 2  2  2  2  3  2  5  2  - {X. + Xj+X +^- - [ X 2  3  2  1 \  2  U  Z  wcos(<£ + a) + X wsin(* + a)J) 3  (A3.20)  The maximum f o r P  w  o c c u r s a t <j> =0  since  -j- (X wcos(4>+a) + X wsin($*a)) 2  3  *  (A3.21)  = -wX sin(tf>+a) + w X c o s ( £ a ) 0 2  if  and o n l y  i f 4> =0.  3  At t h i s  point  +  s  (the L o r i g i n )  166  f  Pwmax = -{x.'+.tp +  ,  J/2  J'2  ) } - { X , + I D - £-)'} 2  2  2  ^ { X i ' + D * ^ - +Dw}  2  1/2  8  -{•X. + D + ^ ,  8  1/2  S | R O + ROW sin/9} 2  -Dw} 1/2  -  |R  2 0  - RoWSin/3 } (A3. 22)  where  E  2  = Xi  2  + D  PWmox  and we assume  2  =  (Ro +  W«D,X, •  I t follows  " (Ro-  (A3.23)  i f Wsin^ « 1 .  Thus t h e a s s u m p t i o n i s s a t i s f i e d  B e c a u s e o f i t s g u a s i - p e r i o d i c i t y we s h a l l  F(t). Thus t h e r e t a r d e d  time  that  take  Ae'" ' 0  derivative (A3.24)  F'(t) where  A  «  Ae  i s an a r b i t r a r y a m p l i t u d e ,  expressed  i n cycles  relative  to  the  has  been f a c t o r e d  can  be n e g l e c t e d The  -i47rP(e ,<£,Xi)  which L origin  out.  P i s a phase d e l a y  determines  the  retarded  function potential  ( s e e b e l o w ) , and t h e t i m e d e p e n d e n c e  The i i n d i c a t e s a "nc/2  phase  shift  and  in this calculation.  effective  field  strength  a s measured by t h e r e c e i v e r  167  antenna a l s o gain  factor  y .  weights the c o n t r i b u t i o n  d/o A W  r  GTGR  2 ir c  where  the  Finally, <*  y  dependence o f #  with respect  R  - i 4 i r P ( 0 , <*>,X,)_  e  a n d c/> on J and r e c e i v e r  to the linear  K / G (e,a +4>) G (0,a +4>) J R R  by  a  T  (A3.25)  R  i f the t r a n s m i t t e r  and a  T  scatterer  Thus  G^(^,4j'  =  from t h e  T  R  w i t h K = cj Aw/2-nc.  R  E  z  = 2  scatterer  coordinate  + D2 + X,  L  i n A3.5.  a n t e n n a e a r e r o t a t e d by then  - i 4 * P ( g , <fr,X,) ^  c  For the $ ,  0  are as stated  (A3.26)  system since  (A3.27)  z  and (E - CP) 2 = D2  + X.2  (A3.28)  then  CP = ( L + D + X. )" - ( D +X, )" 2  2  {  I  2  2  2  D 2  2  2  2  D 2  1/2  1/2 "V  = X.{(£ +tan /3 + l)" - (tan /3+l)" } 2  2  2  2  = X,{u +sec /3)" -secyS } 2  The K i r c h h o f f  2  2  i n t e g r a l may be r e w r i t t e n  2  (A3.29)  168  *  = X /'G(e' a +^G(a a +*)co.«e' Xi ^ l  l  T  R  i 4 , r P l 0 ,  *  , X , )  d€  1  (A3.30)  where  the antennae  gain  functions  have  been  assumed  to  be  identical.  A3.3  The e  _•. 4 t t P  NUMERICAL  integral  i s a rapidly  become  the  inverse  function  RATIONALIZATION  i s  not  yet  varying  integrating o f P.  numerically  function  variable  of  t j .  which  For a given  t r a c t a b l e because We  wish t o l e t  reguires  Xi , ft we  having  dP the  have (A3.31)  X,{u  2  + sec £)" -sec/j}-= 2  2  P  Then  t;  and  =  ±{(  Y  t  +  s  e  c  £  ,  e  -  sec /3 2  }  1/2  (A3.32)  169  =±  A  d  2{^+sec0) I  =  +  The  2  - (|-+sec/8)-72  - sec )9} 2  Xi secff  +  (A3.33)  —  Kirchhoff  K  -  1  integral  then  becomes  oo  'o  cos 8 e  -i4irP  where t h e  integral  duplicity  of  written been  J"  t o r u n from  folded  onto  to the positive that  Q The  has as  _P  •• .  —j7  R  been  a  .  dP  rewritten  function  0 t o oo  2  o f P.  pole a t the o r i g i n  account  The i n t e g r a l - «?  h a s been  to  }  of £  by  value.  0  has  °^- <£)  Again  note  , and t h u s a r e f u n c t i o n s  o f P.  i s now i n a n u m e r i c a l l y i s removable  f o r the  l i m b by a d d i n g G (6 "V- j>)G(fy  cf> a r g u m e n t s a t t h e same P  integral  to  The i n t e g r a l f r o m  the positive  and <j> a r e f u n c t i o n s  (A3.34)  t r a c t a b l e form.  subtracting  The  170  G(^,a )GC^,a )cosi8e" T  i 4 , r P  R  from t h e i n t e g r a n d s i n c e  < v  /^"  (A3.35)  0  as P tends t o 0  Ro P FVl *  f Ro I P'  17  p Note t h a t  a factor  from t h e d u p l i c i t y  o f two h a s been a t 4> =0.  G(^,« )G(A«R)co8i3j^pi T  = [~^]  (Gradshteyn  absorbed  into  and R y z h i k ,  radical  The v a l u e o f t h e p o l e i s  e  , 4 , r P  dP  • (2X,sec/5)"  G^ « )G(/?,a )cos^(2Xisec^)" v  the  T  R  a  2  1965, p.420, eg'ns 3.757.1 & 3.757.2)  Set  J(P)  = {G(e,a +^)G(0,a +</>) T  R  + G(d,a -«/>)G(e,a-<^) } T  Ro < ' > ~D~ f2Ro"l ^ - T n , - -G (0, a ) Gl0, « ) cos/3 [-^-J A3  • cos8 •  l/z  T  R  with  *— ^  sec and  37  0  = sec P ( I + ——)  (A3.38)  171  1/2  tan < / >  Ro P  A3.38 and A 3 . 3 9 . f o l l o w  tan 0 = £ 2  2  — sec 0 = £ 2  2  from  A3.5 and A3.32.  A3.5  2  + sec /3 2  I  X.secfl= P + X.sec/3 = P + Ro rPjhRoi  A3. 5  From  + tan /3  — X.(sec0 - sec/3) = P  A l s o from  (A3.39)  esc P  = sec/3  P + Ro Ro  = sec  172  tan<£ = £ cot £ -~ tan * = £ cot /3 2  2  =  + sec/3) - sec ^} cot/3  2  2  f _ L l + — sec/3} cot /3 Ax, X. P  I+  j  <.Xisec/3V  2  = { X, sec /3  2  2  2  P  l  2  2  I  +  + —] cot ^sec £ X.secfl' 2  2  ZR< csc /3  csc /9  2  2  Xi  —  tan  {  imaginary  I+  2R<  NUMERICAL  N t o N+ j .  can  2  2  csc/S  R<  Consider  we  Ro  sec /3  <f>  A3.4  intervals  2  a full If  we  ANALYSIS cycle break  of P, i . e . e ' ^ ^  where P goes f r o m  up  into  7 7  the  (N^N + 1/8) , (N+1/8,N+1/4), evaluate terms.  J(N+3/8)=J3,  the  inteqral  Call  J (N+1/2) = J *  piecewise  linear  evaluated  as f o l l o w s  2  interval  (N+1/4, N+3/8) ,  piecewise . f o r  J(N)=JO,  and  J(N + 1/8)=J*,  assume  on t h e s u b i n t e r v a l s . (see F i g .  A3. 2) :  that  the  four  equal  (N+3/8,N+1/2)  the  real'  and  J(N+1/4)=J2,  function J i s  Then t h e i n t e g r a l  may  be  J(N)  J(N+|)  J(N*^)  mm J(N*f).  •  •F(N*J)  FIG. A3.2 PICTORIAL  KIRCHHOFF OF  DIFFRACTION  NUMERICAL  MODEL  174  B e a l component  =  IN.N++)  J(J°+8PAJ°)cos4irPdP o - /(J' +8PAJ- )sin 4irP dP  (N-hJ-.N+i)  o  - / (J + 8PAJ )cos4 7rP dP  (N-+-J.N + i ) (N + f , N +  Imaginary  J  2  -1/8  i)  component  2  +J (J +8PAJ )sin 4irP dP 3  3  (A3. 40. 1)  =  - / ( J ° + 8PAJ°)sin 4irP dP o i/e  - J (J o +  +8PAJ')cos4irP dP  1  f  1/8  /  ( J  2  +8PAJ )sin 2  4TTP  dP  • 1/8  +J  where  A J * = J*» + i By c h a n g i n g  (A3.40.2)  (J + 8 P A J ) c o s 4 » P dP 3  3  - J". to v a r i a b l e  x=8P, t h e e i g h t  components  become  175  Beal  components:  i  Aj°  fx  dx  / (J '+ x A J ' )sin -fx dx  i  1  T  - i  I (J + x A J 2  + i j  Imaginary  + x AJ°)COS  (J  + xAJ  8  2  )cos f x dx  3  ) sin f x dx  components:  i -  (J° + xAJ°)sin  if  f x  dx  -fx  dx  o  - iJ  Noting  that  +  i  +  T  o  (J  /'(J  J  + xAJ'  1  )cos  + xA J )sin  2  2  (J + 3  XAJ  3  )C0S  f x d x  X dx  (A3.41)  176  / cos-^xdx >  =  /sin - ^ x d x  o  I  O  /-j-sinydy  =  /  Tycosydy  =  \  [cosy + ysinyj^ 7T/2  w;/2  ^ x s i n -f x d x  •J  * y s i n ydy  the  eight  Real  components:  4  =  [sin y - y c o s y ]  (A3. 42)  terms reduce t o Imaginary  s V ( J ° + AAJ } 0  - «V (J +AAJ Z  Z  (J +BAJ 3  3  F  rV (J  1  +AAJ ) 1  )  +  )  .+ t ± F ( J + A A J  where A=(1-§.) and B = ( | 0 • -ir  components:  - .•^ (J° + B A J ° )  - ^ ( J ' . + BAJ')  + ^  v IT  */2  /xcos-fxdx  =  (J' + B A J ) 2  3  Reformulating  3  )  (A3.43)  i n t e r m s o f the J  w  ,  s  177  Seal  Imaginary  components:  •rir{ J ° ( I - B ) + J ' B  { J ° ( l - A)+ J A 1  -  J  (I - B ) - J  1  2  -  B  +  J  2  5  3  ( l - B ) + J  4  J ' ( I - A ) - J  A  2  + J (I-B) +J B  -J (I-A)-J A 2  components:  8  (A3. 44) +  B }  J  3  (I -  A)+J  4  A}  These r e d u c e t o  Eeal  Imaginary  components:  I  { . J ° ( l - A ) + J'(A+B-I)  J°(l-B)  + J'(A-B-l)  + J ( ! - A - B ) + J (l+B-A)  + J ( A - B-l) + J ( l - B - A ) 2  components:  2  3  J  J (B)} 4  4  3  (A)} (A3.45)  But A +B —I = I - A - B = 0 A - B - l = - -V" jo  and J * o v e r l a p  components  odd  n  on  consecutive  contributions  components e v e n n c o n t r i b u t i o n s have  coefficient  integral  l / - ^ .  which a s s i g n s  2  Thus  cycles. vanish  vanish.  f o r real  and f o r imaginary A l l sustained  a numerical  a s i n g l e summation  Thus  term  formulation t o each  terms of the  piecewise  FIG.  A3.3  FUNCTION "J"  FOR  REFLECTOR  ANTENNA  X, = 750,  a  CORNER  =15°, 6= 10°  TX.9  50  100  PHASE  150  200  250  (P. in cycles) oo  179  linearly  *  "  weighted q u a r t e r  >^  { [ ^ ]  G  (  cycle  0 . V  G  o f the integrand  ^ V  (  c  o  s  0  l  2  * '  S  e  c  /  i s  3  )  '  l  2  P=l  (A3.46)  A3.5 PHYSICAL Equation radiator  REALIZATION  A3.18 i s  an  exact  solution  f o r the isotropic  since  ff F'(t- 2R/c)_  -I  2 i r C ^  -I  f  X,  ,  z  f  0  R  xTS  - ^ f X,c ->  F  0  '  (  R t  2  R  /  c  )  "  s d S d  *  SdS  f ° V ( t - 2 R / c ) dR Xi  ^ F(t-2X,/c) 2 C  X,c  2  F'(t-2R/c)  0  2^1 i  = — Xic  d  X  =  F  (  " ' 2X, t  2  X  /  c  )  (A3.47)  We  c a n show  large  that  A3.18 i s a l s o  class of anisotropic  a reasonable expression f o r a  radiators.  Assume  that  a  radiator  180  has  a cos 6 d i s t r i b u t i o n .  n\  r r F'(t-2R/c)  -I  =  ¥  (t)«  by  z  Q  A  ~  OO  I  Integrate  Then  F'(t-2R/cUos 0  f  2  dR  (A3.48)  parts  x4{|-  F(t - 2X,/c) +  |/^F(t-2R/c)dR}  { / F1t-2R/c)dR+c/^-F(t-2R/c)dR  But  |F«| = <*MF|,  neglected.  and  ~  <:< — °  r r '(t F  2TTC^  C  t h e same a c c u r a c y distribution  sin0cos<£>  are  perpendicular  the  of  or  we c a n show sin£cos<£  as t h e c o s 6 a  vertical  complementary  horizontal  dipoles.  (A3.50)  2X,  •  sinc5sin 4 »  sin B ,  F(t-2X,/c)  .„  X,R  By an i d e n t i c a l p r o c e d u r e  the  , h e n c e t h e s e c o n d t e r m c a n be  -2R/ )  F'(t-2R/c)  within  (A3.49)  Thus  #*i  with  }  that  for  radiators  distributions  distribution. dipole.  Sin 6  Sin9 sin  distributions These l a s t  ^P(t)=0  three  for  is and two  solutions  181  comprise  a  solutions. with  basis By  set  for  linear  constructing  combinations  i t s own X, , we c a n c o n s t r u c t  This i s an important  result since  V l t ) = Gw(,0 , - ),G~ X(~0,, - ) , V  R  a large  class  i t means  that  F  t  t  2  )  " <  2  F  2TTC  is  a  reasonable  realizable If radiator  P  T  from  '  X  /  c  R - » ^ '  approximation  oscillating  of  each  solutions.  )  (  ( t  Z  R  1  dipole  of a r b i t r a r y d i p o l e s ,  //G (g,0)G (g^) ' T  arbitrary  for  X  (  R  /  C  )  61  (A3.51)  R  any  antenna  physically  dipoles.  i s t h e peak r a d i a t e d  power,  then  for  the  isotropic  over a p e r f e c t r e f l e c t o r (A3.52)  Then  2*c XlC  J  J  • Xi  /  P  T  2X^ and  4  V  r  X,R  4 7T  V  Zo  4*  -i«(t 6  - 2-X./.C)  (A3.53)  182  *(t) Y  V-^^  =  peak  2X«  (A3.54)  4*  and  x  = p.  T  A /4-TT  where  i  s  2  (A3.55)  64TT X, 2  the r e c e i v i n g  2  antenna's e f f e c t i v e area  (Jasik,  1961) . For  the a n i s o t r o p i c  radiator  over a p e r f e c t  reflector (A3.56)  2  P  R  = G (0,-)G (0,-)-P £ ^ 64ir X. r  R  T  z  Z  ;  z  and  P  x  =  For  Zo ' "'peok'  4*  T  z  IsTxT- [ z ^ J  the ribbon  -i« (t -2R/c)  2  [J7 T<3R  scatterer,  G  6  combining  R  iz].  A3.57 with  A3.34  183  r  P  R  f  2  W\ /°° -i4irp I + Ro/P . 47X? 2 ^ 7 K - G G G ) c o s * e ^ — — ^ dP n  T  R+  T  D  R  (A3.58)  Noting  t h a t i n the nondimensionaiized  invoking  s y s t e m cj /2-trc=1. a  A3.46 -  " '  Then  by  '• • • •  1/2  P R V!!  v/X +  ici-i.^oJCP/8)  e 'f  o - , P  r2X> sec ft j  Q  }| (A3. 59)  where t h e i m p l i c i t  d i m e n s i o n l e s s u n i t s have b e e n  included.  

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