An analysis of opportunistic forwarding for correlated wireless channels

Abstract

A variety of forwarding strategies have been developed for multi-hop wireless networks, considering the broadcast nature of the wireless medium and the presence of fading channels that result in time-varying and unreliable transmission quality. One such strategy is opportunistic forwarding, which exploits relay diversity by opportunistically selecting an overhearing relay as a forwarder. Prior work has studied the performance of opportunistic forwarding for the simplified scenario of uncorrelated wireless channels. In this paper, we consider a more realistic scenario of temporally correlated wireless channels; the wireless channel is modeled as a Rayleigh fading channel and its temporal correlation as a modified Bessel function of the first kind and zeroth order. We use these models to develop a simple Markovian model to analyze the performance of opportunistic forwarding for correlated wireless channels for the case of linear networks. We then demonstrate via numerical evaluation the diminishing performance of opportunistic forwarding with increasing channel correlation.