Hop-by-Hop Routing Strategy for Multihop Decode-and-Forward Cooperative Networks

In this paper, focusing on multihop decode-and- forward cooperative networks, a hop-by-hop routing strategy is designed to optimize the end-to-end outage performance when only knowledge about the mean channel state information (CSI) is available. In particular, by only utilizing the mean CSI at the current hop, a novel optimization metric is devised to select the best relay on a per-hop basis. The outage analysis illustrates the advantage of the proposed hop-by-hop routing strategy. In addition, a decentralized implementation scheme with minimal overhead is presented. Under realistic propagation conditions, including the effects of path loss and Rayleigh fading, the end- to-end outage performance is evaluated. Simulation results show that, when only the mean CSI can be exploited, the proposed hop-by-hop routing strategy can provide a good tradeoff between performance and overhead.