An Adaptive Procedure for Impulsive Noise Mitigation over Power Line Channels

Amplitude clipping is one of the ways to fight against transmission impairments due to impulsive noise. In a recent study, in order to cope with empirical threshold determination, we used a Receiver Operating Characteristic (ROC) analysis to derive a closed form expression of the optimal threshold. In this paper we show that this ROC analysis also corresponds to a maximum likelihood (ML) criterion. Then, we evaluate, over power line channels, the efficiency of the clipping operation based on this ML decision. Furthermore, an adaptive scheme is proposed for automatic impulse mitigation over such channels. The adaptive procedure consists in estimating the impulsive noise parameters and updating the clipping threshold through ML optimization. The proposed scheme is finally evaluated over HomePlug AV (HPAV) physical layer.