EEM-LEACH: Energy efficient multi-hop LEACH routing protocol for clustered WSNs

Recent technological advances in communication sector have resulted in the development and improvement of wireless sensor networks consisting of low cost, low power and smaller multi-functional sensor units. Limited battery life of sensor nodes is one of the critical issues in wireless sensor networks. Energy dissipation for data transfer from nodes to base station is the crucial cause of energy depletion. A wide variety of routing protocols were introduced to increase the lifespan of the network and the most efficient scheme is clustering of nodes within the network that works on the principle of divide & conquer and data aggregation. This paper proposes an energy efficient routing protocol EEM-LEACH that discovers a multi-hop path with minimum communication cost from each node to the base station. If the communication cost for direct data transfer is minimum, nodes close to the base station can send data directly to the base station thereby preventing them from dying soon. Only nodes with maximum residual energy and minimum energy consumption can become cluster heads since each node's residual energy as well as average energy consumption is considered for the selection of cluster heads. No global information is needed because cluster formation and multi-hop path selection are distributed. As communication cost per packet is minimized and relay nodes have more residual energy, the network lifetime can be improved.