Taking Full Advantage of Multiuser Diversity in Mobile Ad Hoc Networks

Multiuser diversity has been shown to increase the throughput of mobile ad hoc wireless networks (MANETs) when compared to fixed wireless networks. This paper addresses a multiuser diversity strategy that permits one of multiple one-time relays to deliver a packet to its destination. We show that the throughput of the original single one-time relay strategy is preserved by our multi-copy technique. The reason behind achieving the same asymptotic throughput is the fact that, as we demonstrate in this paper, interference for communicating among closest neighbors is bounded for different channel path losses, even when goes to infinity. We show that a significant delay reduction is possible by multi-copy relaying when is finite. Furthermore, we find that the average delay and delay variance for both the one and multi-copy relay strategies scale like and , respectively. We derive an approximation of the delay for multi-copy forwarding scheme and demonstrate that this approximation is very close to simulation results in MANET systems.