Hierarchical MIMO: A clustering approach for Ad hoc wireless sensor networks

MIMO based communication protocols have been proposed for energy conservation in wireless sensor networks. In this paper we present an energy efficient clustering framework. We implement a hierarchical clusterhead selection algorithm which chooses the clusterheads and the cooperating nodes to achieve high energy gains in cooperative MIMO communication. The algorithm selects the clusterhead on the basis of residual energy of the nodes. The reclustering approach ensures minimum disturbance in the network. The local communication within a cluster takes place via SISO. Each cluster is led by a clusterhead. The clusterhead and cooperative node forward data to the routing clusterheads via 2x2 MIMO. The data is further relayed via MIMO until it reaches the base station.We evaluate our proposed scheme on the basis of analytical and simulation results. The results show significant energy conservation if packets are routed via hierarchical MIMO.