Minimum Outage Routing in Cooperative Multi-hop Networks

We consider the joint routing and cooperation diversity problem in multi-hop networks, for which we seek to optimize the end-to-end outage. Simplifying the network structure via partitioning and identifying a set of nodes in each partition, we devise a routing strategy based on cooperative relays in decode-and-forward mode. In particular, this sub-optimal routing algorithm yields the best possible path between the source and destination pragmatically considering the outage probability as the optimization metric. To reduce the amount of required channel state information and the path computation complexity, we introduce a simplified realization, referred to as L-relay ad-hoc, in which a relay selection method based on channel gains is applied at each hop. We evaluate the performance of the proposed methods under practical conditions. Simulation results show that the proposed sub-optimal strategy can perform very closely to the optimal strategy with less channel information requirement, and the L-relay ad-hoc method can also demonstrate a good performance with significantly reduced complexity.