Performance analysis for MIMO systems using zero forcing detector over fading channels

In the paper, the performance of multiple-input-multiple-output (MIMO) systems using a zero forcing detector is studied over Rayleigh and Rice fading channels. Approximation to the distribution of non-central complex Wishart distribution is used to derive the distribution of the post-detection signal-to-noise (SNR) ratio. A closed-form expression of bit error rate is obtained in terms of the hypergeometric and Gamma functions. The performance of MIMO systems under the scenario that the individual sub-channels are correlated is also investigated. It is shown that, for the exponential correlation channel model, an increase in channel correlation between the transmission paths results a decrease in SNR at the receiver. It is concluded that with the same SNR at the receiver, the performance of MIMO systems over a Rice fading channel degrades compared to that over an independent and identical distributed (i.i.d.) Rayleigh fading channel.