Distributed Optimization of Transceiver Weights in MIMO Two-Way Multihop Networks

We investigate the joint optimization of power allocation and transceiver weights in multiple-input multiple-output(MIMO) two-way multihop networks. The objective is to maximize the minimum weighted signal-to-interference-plus noise power ratio (SINR) of the multihop links while satisfying general linear power constraints at the transmit nodes. First, we derive a distributed power allocation algorithm by extending the notion of link SINR metric and analyze its convergence and optimality. Using that result, we propose an alternating optimization algorithm for solving the more complex MIMO transceiver weights optimization. We compare its performance against those of centralized and conventional schemes through numerical simulations. Our results show that the proposed algorithm provides considerable improvement to the end-to-end rate of multihop networks. In fact, it achieves, with low complexity and low coordination overhead, a rate performance close to an upper-bound that was obtained from a centralized optimization with a relaxed power constraint.