Error Probability and SINR Analysis of Optimum Combining in Rician Fading

This paper considers the analysis of optimum combining
systems in the presence of both co-channel interference
and thermal noise. We address the cases where either the
desired-user or the interferers undergo Rician fading. Exact
expressions are derived for the moment generating function of
the SINR which apply for arbitrary numbers of antennas and
interferers. Based on these, we obtain expressions for the symbol
error probability with M-PSK. For the case where the desireduser
undergoes Rician fading, we also derive exact closed-form
expressions for the moments of the SINR. We show that these
moments are directly related to the corresponding moments of
a Rayleigh system via a simple scaling parameter, which is
investigated in detail. Numerical results are presented to validate
the analysis and to examine the impact of Rician fading on
performance.