On capacity of relay-assisted communication

In this paper, we study communication in wireless networks where there is no central control available, like wireless ad hoc and sensor networks. We derive the outage probability of multi-hop communication and study it in detail for a simple linear topology. The results indicate that an appropriate choice of route can lead to large performance gains over alternate routes. In the second part of the paper, we consider the problem of estimating outage-minimizing routes using channel measurements. We show that finding the optimal routes reliably requires many independent channel measurements, which is equivalent to sending multiple route discovery requests. The large overhead in route discovery can prove to be counter-productive in networks which transmit information at the same time-scale as the mobility of nodes.