Opportunistic relaying in ad-hoc networks for throughput improvement

Abstract

In this paper, n mobile source-destination pairs and m relay nodes are considered in the same frequency band. In the previous works, it is assumed that the ad hoc nodes were fixed which causes users with lower SINR cannot communicate through relays. Here, we propose a scheme in which the mobility is managed in opportunistic manner to let ad hoc nodes satisfy a lower SINR threshold to be active and transmit successfully. We compute new SINR threshold for n source-destination pairs and m relays distributed uniformly and randomly on the constant area. This threshold is achieved as 1-√(log n/n)/R which causes the lower bound of the throughput to be increased. Also, we investigate the required time for movement of nodes and estimate it as Θ(√(log n)). This time is negligible compared to queuing delay term which is computed previously as in the order of Θ(n). Both of the simulation results and analytical calculations show that we achieve the better throughput while the delay does not change meaningfully.