Cooperative Opportunistic Routing Using Transmit Diversity in Wireless Mesh Networks

We propose a new high performance forwarding scheme, denoted transmit diversity based cooperative opportunistic routing (TDiCOR), that efficiently exploits multiuser and transmit diversity to improve the overall throughput in wireless multi-hop networks. Neighboring nodes cooperate through simultaneous transmissions in a MISO fashion in order to overcome the destructive effects of fading. TDiCOR uses distributed transmit diversity to increase the robustness of acknowledgements as well as data transmissions while preserving the opportunistic nature by using multiple candidates for packet relaying. We present measurements from a wireless testbed which suggest that cooperation using transmit diversity is feasible even with today´s off-the-shelf hardware. At the instance of TDiCOR, we demonstrate how to realize the idea of cooperative opportunistic routing as an operational protocol and present very promising simulation results. TDiCOR outperforms traditional routing (i.e. DSR) in typical outdoor scenarios in terms of throughput by 30% and by 50% in indoor scenarios with high shadow fading, without consuming additional bandwidth or additional hardware resources.