Coverage and Throughput Enhancement in MIMO Cellular Networks via Cooperative Relaying

Obumneme Godfrey Okeke
One of the major challenges of broadband cellular systems is delivering high data rates to the users, especially those at the cell edges. In this thesis, transceiver designs and scheduling algorithms for enhancing cell-edge user experience in emerging and future broadband wireless cellular networks are investigated. In particular, the use of fixed infrastructure-based non-regenerative and altruistic (i.e., not having their own data to transmit) relays for coverage extension (at high data rates)
more » ... at high data rates) in cellular networks with multiple antenna transmitters and receivers is considered. In order to mitigate the high interference jeopardizing the high data rate promise of multiple-input multiple-output (MIMO) spatial multiplexing in cellular networks, coordinated multipoint (CoMP) transmission/reception is employed. Leveraging MIMO, CoMP and relay techniques in a unified manner, we jointly design the input covariance and relay beamforming matrices to maximize the system data rate. For the single-cell MIMO downlink, uplink-downlink duality is first proved and then employed to design the downlink parameters from more tractable uplink channel. For the multi-cell MIMO network, interference mitigation is incorporated into the relay designs in order to decouple the correlated relay transmissions due to interference from unintended sources. Furthermore, we propose novel low complexity joint user-relay selection/scheduling and/or association strategies to further improve the system performance, which lead to low complexity and overhead. Simulation results demonstrate the effectiveness of the proposed schemes. The favorable performance and low complexity of the proposed schemes make them very attractive for possible implementation in emerging and future broadband wireless networks.
doi:10.7939/r3dv1ct59 fatcat:c5yd7bunzfa3hcs7uehxaeya4u