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UBC Theses and Dissertations

High-efficiency millimeter-wave signal generation for communication, imaging, and radar applications Tarkeshdouz, Amirahmad

Abstract

Over the last decade, integrated circuit technology has witnessed a surge in interest toward millimeter-wave (mm-wave) frequencies (30 to 300 GHz), mainly due to the increasing number of promising applications enabled by and implemented in this frequency band. Imaging and bio-molecular spectroscopy are among the main applications of mm-wave frequencies. The ability to characterize nanostructures could have a dramatic impact on basic research in materials design and biosensing. Many magnetic-resonance (MRI) based imaging techniques used to explore biological structures benefit partly from being carried out at very low temperatures. Lack of transistor models at such low temperatures is a major challenge for circuit design. In the first part of this thesis, we address the fundamentals of signal generation at low temperatures and develop a custom-designed, application-specific signal source for an imaging experiment implemented in a 0.13-µm bipolar/complementary metal-oxide semiconductor (BiCMOS) process. The basics of signal generation outlined in this part can be expanded to include other needs for cryogenic applications. Radio technology has evidenced a rapid evolution with the launch of the analogue cellular systems in 1980s. As technology evolves, so does our expectation on how we could use it. Growing demand for high throughput and capacity on one end, and the ever-increasing desire towards ubiquitous connectivity on the other end, have strained current schemes and standards, calling for alternative novel high capacity systems. To address capacity demands, mm-wave spectrum provides a unique opportunity due to the availability of wider and unpopulated frequency bands which better facilitate high-speed communications. In this context, the emerging 5th Generation Mobile Network (5G) is also expected to use mm-wave bands. However, energy efficiency remains a critical issue for all of these applications and has become an important challenge to deal with in face of higher performance requirements. In the second part of this thesis, we propose circuit solutions and strategies for efficient signal generation at very high-frequency bands and demonstrate state-of-the-art mm-wave signal sources implemented in 65-nm and 0.13-µm CMOS with DC-to-RF efficiencies of around 15%, the highest efficiencies reported to date for CMOS oscillators operating in the vicinity of and beyond 100 GHz.

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Attribution-NonCommercial-NoDerivatives 4.0 International