Energy Efficient STBC -Encoded Cooperative MIMO Routing Scheme for Cluster Based Wireless Sensor Networks

Wireless sensor network (WSN) requires robust and energy efficient communication protocols to minimise the energy consumption as much as possible. However, the lifetime of sensor network reduces due to the adverse impacts caused by channel fading and interference in WSN. A cluster based cooperative multi input multi output (MIMO) routing scheme is proposed as a solution for this problem. Two MIMO routing schemes are proposed in this paper extending low energy adaptive clustering hierarchy (LEACH) protocol using space time block codes (STBC) to achieve higher energy savings and diversity gain. The first scheme enables multihop transmissions among the clusters through the selection of cooperative sending and receiving nodes in each cluster called as cooperative MIMO LEACH (C-LEACH) protocol. The second scheme incorporates cooperative MIMO communication by letting cluster heads to transmit data to base station cooperatively called cluster head cooperative MIMO LEACH (CH-C-LEACH) protocol. The performance of the proposed cooperative MIMO systems such as C-LEACH and CHC- LEACH are evaluated in terms of energy efficiency and reliability. Simulation results show that tremendous energy savings can be achieved by adopting cooperative transmissions among the clusters employing STBC technique. The proposed cooperative MIMO schemes prolong the network lifetime approximately twice when compared to traditional LEACH protocol.