Multiple-input multiple-output wireless communication systems with cochannel interference

To meet the requirement of very high data rates for wireless Internet and multimedia services, multiple transmitting and multiple receiving antennas have been proposed for fourth generation wireless systems. In cellular systems, performance is limited by fading and cochannel interference from other users. Most of the current studies on multiple-input multiple-output (MIMO) systems assume that the cochannel interference is both spatially and temporally white. In this thesis, we focus on MIMO systems under both spatially and temporally colored interference.; In MIMO systems, diversity gain is effectively achieved by the multiple receiving antennas. Outage performances of several receive diversity schemes are analytically compared for an interference-limited environment in a Rayleigh fading channel. We investigate three diversity schemes: a practical variation of maximal-ratio combining, equal-gain combining (EGC) and selection combining (SC). An exact outage probability expression is derived for EGC by accurately calculating the interference power at the output of the combiner. It is found that the relative performance between EGC and SC depends on the number of interferers and interferer power distribution.; Channel estimation and data detection for MIMO systems under both spatially and temporally colored interference are studied. By modelling interference statistics as being approximately temporally and spatially separable, we propose an algorithm to jointly estimate channel and spatial interference correlation matrices based on maximum likelihood principle. Multi-vector-symbol data detection is developed to exploit the temporal interference correlation. In the case of one interferer operating at a lower data rate, the results show that significant improvement can be achieved by taking account of the temporal interference correlation in data detection.; Information capacities of MIMO channels under spatially and temporally correlated interference are derived. Capacity gains due to the knowledge of the channel matrix and interference statistics at the transmitter are assessed. To achieve these capacity gains, we propose an adaptive modulation scheme exploiting the channel matrix and interference statistics estimated by the receiver. In particular, the impact of channel estimation error and feedback quantization error on adaptive modulation is evaluated for MIMO systems.