System Performance Analysis of Single-Path and Cooperative MIMO Relaying

The demand for even higher data rates in future mobile communications systems calls for new techniques capable of improving the performance of cellular systems. One possibility are relay enhanced cells where additional radio access points without wired backhaul are mounted and served by a base station using in-band resources. Although relaying can significantly improve channel conditions in terms of pathloss and fading, it suffers from a limited link between base station and relay node as well as from the half-duplex operation in which relay nodes retransmit messages. In this work we discuss and evaluate relaying strategies for multiple antenna based systems in terms of average user throughput. The performance of a conventional cellular system is compared with single-path relaying and cooperative relaying where base stations and relay nodes cooperatively serve user terminals.