BER Analysis of Diversity M-PSK Receivers Over the Weibull Fading Channel with Cochannel Interference

In this paper, we conduct a comprehensive study on the performance of dual-branch diversity M-PSK receivers with possibly correlated branches operating over Weibull fading channels in presence of cochannel interference (CCI). We use a characteristic function (CF) based approach to derive exact expressions for the bit error rate (BER) under such conditions assuming both selection combining (SC) and post-detection equal gain combining (EGC) diversity schemes. For the EGC correlated branches case, due to the lack of existence of a closed-form expression for the CF of the sum of two correlated Weibull random variables (RVs), we revert to using the Padé approximation (PA) technique to approximate this CF by a rational function and hence, an approximate BER expression is obtained. Various results pertaining to the effect of fading severity of both the desired signal and the interferers, and the effect of correlation between diversity branches for different M-PSK modulations are presented. Our results are verified by comparison with Monte Carlo simulations and excellent agreement is observed.