Statistical properties of the EGC output SNR over correlated Nakagami-m fading channels

Previous studies have addressed with the performance analysis of L-branch equal gain combining (EGC) systems over independent Rayleigh- or Nakagami-m fading channels. In this paper, important statistical parameters, such as the κ-moment, the κ-central moment, the skewness, and the kurtosis of the output signal-to-noise ratio (SNR), in predetection EGC systems operating over correlated Nakagami-m fading channels are studied. Simple closed-form expressions for the mean and variance of the output SNR are presented and it is shown that our general results reduce to the specific noncorrelative fading case previously published. Moreover, significant performance criteria such as the amount of fading and the spectral efficiency in the low power regime, are investigated. Numerical results and simulations are presented to check the validity of the proposed mathematical analysis and to point out the impact of the fading correlation, the input SNRs unbalancing as well as the fading severity, on the EGC performance.