EXACT SINR CALCULATIONS FOR OPTIMUM LINEAR COMBINING IN WIRELESS SYSTEMS

This paper presents an exact derivation of the statistical distributio n of the signal to interference-plus-noise ratio (SINR) for optimum li near combining in wireless systems with multiple cochannel interferers , Rayleigh fading, and additive white Gaussian noise. The distribution of the SINR is shown to be remarkably simple and leads to bounds on t he bit error rate and outage probabilities which are tighter, simpler, and more robust than any previous results. The simplicity of the SINR distribution permits extremely fast computation of outage probabiliti es for any number of interference channels and diversity levels. Hence for wireless systems it enables performance studies to be performed o ver a much wider range of conditions, such as shadow fading, specific channel allocation methods, etc. Previously such studies were extremel y limited due to the intensive computational requirements of simulatin g these systems.