Performance analysis of MIMO systems with co-channel interference over Rayleigh fading channels

Relying on the Khatri distribution of the largest eigenvalue of certain quadratic forms in complex Gaussian vectors, we develop an analytical framework for the performance analysis of multiple-input-multiple output (MIMO) systems subject to co-channel interference and operating over Rayleigh fading channels. We consider interference limited systems in which the number of interferers exceeds or is equal to the number of receiving antenna elements and we present new closed-form expressions for the probability density function of the output signal-to- interference ratio and for the MIMO systems outage probability. When applicable these expressions are compared to the special case previously reported in the literature dealing with the performance of single-input-multiple-output (SIMC) systems. As a double check these analytical results are validated by Monte-Carlo simulations and as an illustration of the mathematical formalism some numerical examples for particular cases of interests are plotted and discussed. These results show that, given a fixed number of total antenna elements and co-channel interferers, (i) SIMO systems will always outperform multipleinput-single-output systems and (ii) it is preferable to distribute the number of antenna elements evenly between the transmitter and the receiver for an optimum performance.