Performance Analysis of Multi-Branch Non-Regenerative Relay Systems with EGC in Nakagami-m Channels

The end-to-end performance of multi-branch dual-hop wireless communication systems with non-regenerative relays and equal gain combiner (EGC) at the destination over independent Nakagami-m fading channels is studied. We present new closed form expressions for probability distribution function (PDF) and cumulative distribution function (CDF) of end-to-end signal to noise ratio (SNR) per branch in terms of Meijer's G function. From these results, analytical formulae for the moments of the output SNR, the average overall SNR, the amount of fading and the spectral efficiency are also obtained in closed form. Instead of using moments based approach to analyze the asymptotic error performance of the system, we employ the characteristic function (CHF) method to calculate the average bit error probability (ABEP) and the outage probability for several coherent and non-coherent modulation schemes. The accuracy of the analytical formulae is verified by various numerical results and simulations.