Performance analysis of power line communication systems with diversity combining under correlated lognormal fading and Nakagami noise

In this study, the authors evaluate the bit error rate (BER) performance of multichannel power line communication (PLC) systems under lognormal fading and Nakagami-m background noise. The information signal propagates over two parallel, but correlated channels while maximum ratio combining and equal gain combining are implemented at the receiver side. By appropriately approximating the tail of the probability density function of a single Nakagami-m noise term and of the weighted sum of two Nakagami-m noise terms, they derive accurate expressions of the BER. They prove that single-channel and multichannel PLC systems both benefit from an infinite diversity order and that this quantity increases logarithmically with the signal-to-noise ratio. In this case, the advantage of the diversity combining techniques resides in their impact on the average energy of the fading gain; a quantity that they derive analytically by applying the lognormal-sum approximation.