Performance analysis for a multi-branch nonregenrative relay system with MRC in Nakagami-m channels

In this paper, the performance of multi-branch dual-hop relay systems with maximal ratio combining (MRC) receiver operating in Nakagami-m fading channels is analyzed. We derive closed-form expressions for the moments of signal to noise ratio (SNR) at the output of maximal ratio combiner. From these moments, other important performance figures such as average output SNR, amount of fading (AoF) and spectral efficiency (SE) can be calculated. The average bit error probabilities (ABEP) for various coherent and non-coherent modulation schemes and outage probability (P
_out
) are also obtained by using the moment generating function (MGF) and characteristic generating function (CHF) approaches, respectively. The mathematical analysis is verified by various numerical and computer simulations, which show the accuracy of the expressions for both ABEP and P
_out
.