Improved cluster head election protocol (ICHEP) for heterogeneous wireless sensor networks

The lifetime of a wireless sensor network is constrained by the limited energy and processing capabilities of its nodes. The network lifetime can be maximized when the energy of different nodes of the network depletes uniformly during the sensing, processing and forwarding the data to the sink. Since, the energy required per bit for communication is around two orders of magnitude higher than computation, hence the task of sending the sensed data to the sink requires proper designation of nodes for this energy intensive task. In this paper we have considered the heterogeneity of the sensor network in terms of the initial energy of the sensor nodes. We assume that some of the nodes are having more energy than the normal nodes. Due to the heterogeneity present in the network, it is not possible to use the same protocol which is used for the homogeneous network. In this paper, the proposed cluster head selection technique uses the additional energy of the sensor node to increase the life time of the sensor network. The technique is a modification of LEACH (Low energy adaptive clustering hierarchy) protocol which is hierarchically clustered protocol. Our protocol also removes the instability caused with the death of first node.