Optimal MIMO beamforming based topology management for interference minimization in MIMO wireless sensor networks

In this paper, we present a novel beamforming based scheme for interference aware topology management in MIMO Wireless Sensor Networks. Topology Management techniques are aimed at achieving network topologies that guarantee energy efficient connectivity and coverage, thus leading to maximization of the lifetime of the WSN. In this context, we propose a scheme which finds a minimum spanning tree together with the optimal set of beamformers at the MIMO equipped wireless sensor nodes. For this purpose, we formulate a link metric which takes into consideration the interference at other nodes belonging to its coverage area in the WSN. Subsequently, employing the formulated metric in the WSN, we find a spanning tree which maximizes the sum-metric, thus minimizing the interference. We also determine the optimal set of beamformers considering multi-node interference and cooperative transmission among sensor nodes in the WSN spanning tree based topology. Simulation results demonstrate that the above schemes lead to a significant improvement in the overall SNR of the links in the WSN topology.