Optimal Power Routing for End-to-End Outage Restricted Distributed MIMO Multi-Hop Networks

This paper investigates the optimal power routing problem in relay-based cooperative networks, where the relays are arbitrarily positioned. We generalize the standard shortest path routing algorithm (GSPRA) to find an minimum-power distributed MIMO multi-hop route from a source to a destination while satisfying a given e2e outage probability demand. The task of the proposed approach includes how to group relays to virtual antenna array (VAA) and discover the optimal multi-hop path. Instead of using per hop (or link) constraint, which is assumed by most of the existing routing algorithm, an e2e outage probability constraint is assumed for more relevance and freedom in practical systems. Under the concept of virtual node and virtual link, an efficient power allocation solution for general distributed MIMO multi-hop networks is used to calculate link costs for the shortest path algorithm. The proposed routing approach can fully exploit the merits of both cooperative communications and multi-hop transmissions. The significant power savings due to the proposed approach in comparison to the existing algorithms is demonstrated by numerical results.