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Resource allocation with multi-cell coordination in wireless networks

University of British Columbia

To meet the growing demand of mobile data service with limited radio resources, the cellular architecture has evolved from single-cell networks towards multi-cell networks. In multi-cell networks, the spectrum is reused by multiple adjacent cells to increase the spectral efficiency. As a trade-off, interference is introduced among the cells, which limits the achievable data rates for users who experience significant inter-cell interference. In this thesis, multi-cell coordination is applied to mitigate interference, and several resource allocation mechanisms are proposed to improve the system performance for various multi-cell networks. First, a downlink scheduling mechanism is proposed for a multi-cell multiple-input multiple-output (MIMO) network. This mechanism dynamically selects the users to be scheduled and the corresponding MIMO transmission strategy to optimize a utility function. Both centralized and distributed algorithms are developed, and an efficient rate adjustment method is proposed to improve the system throughput when the channel state information (CSI) is imperfect. Next, a network configuration mechanism is developed for two-tier macro-femto networks. In this mechanism, coordination is applied for different network configuration processes such that access control, spectrum allocation and power management are performed sequentially at the base stations and users, respectively. This mechanism is modeled as a multi-stage decision making process and the desired decisions are obtained using a multi-level optimization approach. Finally, coordination among multiple service providers for resource sharing is studied in cloud-based radio access networks (C-RANs). A multi-timescale resource sharing mechanism is designed. This mechanism employs a threshold-based policy to control the inter-cell interference, and defines a new metric for providing resource sharing guarantee for each service provider. It consists of resource allocation processes that are performed at different time scales to deal with traffic demand variation. The proposed mechanism addresses the issue of user mobility by employing a mobility prediction method when optimizing the resource sharing decisions. The performance of the mechanisms proposed in this thesis are evaluated via computer simulations. It is shown that these mechanisms substantially improve the performance for the corresponding multi-cell networks.

Text

2015-10-24

Attribution-NonCommercial-NoDerivs 2.5 Canada

http://hdl.handle.net/2429/54833

Electrical and Computer Engineering

University of British Columbia

UBCV

http://creativecommons.org/licenses/by-nc-nd/2.5/ca/