Unequal Density-based Node Deployment and Clustering Routing Protocol in Wireless Sensor Networks

In order to solve the problem of the hot spots in clustering routing protocols, this paper proposes an unequal density-based node deployment and clustering routing protocol (UDNDC). It has following characteristics. (1) In clusters, member nodes transmit data directly to cluster head, and cluster head can fuse all signals into a single signal. But data from different clusters cannot be fused, and multi-hop forwarding is used among clusters to save energy. (2) In order to balance the energy depletion of nodes, the proposed protocol uses an unequal density-based node deployment strategy and analyzes the optimal node deployment density in different network regions in theory according to energy dissipation model of nodes. (3) It is distributed clustering protocol and doesn’t need overall information during cluster setup phase. (4) Cluster heads are chosen out by their residual energy and rotated periodically. (5) It can ensure quantity stability of cluster heads in each round and fairly even cluster head distribution across the network. Simulation results show that UDNDC can effectively solve the problem of the hot spots and obviously prolong the network lifetime.