ISBN 9783843921732

978-3-8439-2173-2, Reihe Kommunikationstechnik

Zijian Bai
Interference-Aware Receiver Design for Closed-Loop MU-MIMO Transmission in Mobile Communication Systems

302 Seiten, Dissertation Universität Duisburg-Essen (2015), Hardcover, A5

Zusammenfassung / Abstract

In the mobile Internet phase of the Information Age, social development and economic growth have been promoted by the dramatically increased number of mobile broadband personal smart devices in the global cellular mobile communication system. However, the high density of terminals in one cell results in high system load and thereby an interference-rich communication environment, which challenges engineers to construct more efficient systems. Among the technical solutions of this problem in the radio interface and access networks, the present thesis contributes to the signal processing in an efficient receiver in user equipment. Such receiver is aware of spatial co-channel interference (CCI) in a practical closed-loop MU-MIMO (multi-user multiple-input and multiple-output (MIMO)) transmission and achieves desired performance enhancement with low-cost implementation.

With the example system of LTE/LTE-Advanced, the aspects of quantized CSI (channel state information) feedback and spatial CCI aware signal detection supporting closed-loop MU-MIMO are the focuses of this thesis. After giving a deep insight into the linear and non-linear receivers in generic MIMO-OFDM (orthogonal frequency division multiplexing) systems in the mobile channel, different aspects of selecting CSI feedback parameters in closed-loop FLA (fast link adaptation) transmission in LTE-Adv systems are presented. Discussions on the selection procedure, algorithms for individual or combined parameters are elaborated, which results in newly designed mutual information based multi-stage selection method. This method yields desired closed-loop FLA benefits with low computational efforts. While the closed-loop system is further extended by MUMIMO, the study concentrates on the construction of the spatial interference knowledge. Especially, the detection of the CCI precoder vector as the major part of the interference channel is the focus. With the particular consideration of the performance-complexity trade-off, method of moments based detection algorithms with different second moments of the receive signal vectors are derived. Such detection algorithms enable the spatial CCI aware receiver in practical systems.

The major contribution of this thesis is the design of signal processing algorithms that enable an efficient receiver with low-cost CSI feedback and spatial CCI aware detection in the practical closed-loop MU-MIMO transmission.