Research On Routing Protocol For Wireless Sensor Networks-Improvement Of LEACH Routing Protocol

With the development of sensor network technology, Wireless sensor network(WSN) hasbeen great concerned in the network research areas. It is a multi-hop self-organizing networksystem, it consists of a number of wireless sensor node which can communicate wirelessly. Itusually comprises of a perception module,a processor module, sensors, and a battery power.The purpose of these nodes are to monitor a given set of environmental conditions.There are two kinds of routing protocol. The planar routing protocol and the hierarchicalrouting protocol. The planar protocol does not be applied to the present growing with theexpansion of network scale beacuse of the reduction in the speed of dynamic response.Whereas the hierarchical routing protocol can handle this problem vary well. LEACH is themost popular cluster-based routing protocols in the wireless sensor networks. The cluster headrole keeps on rotating to balance the energy dissipation of the sensor nodes in the networks.The function of cluster head nodes are to fuse and collect data arriving from cluster membersand forward the aggregated data to the sink in order to reduce the amount of data.Energy conservation is the primary consideration in wireless sensor networks. Extendingthe lifetime of the wireless sensor networks and balancing nodes’ load are the goal ofdesigning the routing protocol in wireless sensor networks. Classical clusteringcommunication protocol of LEACH was analyzed. In order to extend the lifetime of networkin LEACH, this paper proposes an improved cluster-head election algorithm. Include, If theresidual energy of each cluster-head is lower than the given threshold, cluster-head election isdone in the whole network, this paper introduces a new strategy based on the relative densityof nodes, the selection method of the threshold for electing cluster-head is optimized. If not,the election is done in the cluster, the protocol chooses new cluster-head nodes based on thenode’s residual energy, position,dense grade. Compared with LEACH algorithm, the timecomplexity of the improved LEACH algorithm has not changed much.In this paper, we consider the optimal number of cluster head. Considering the affectionon network performance by the nodes density and the size of area. When the networkcoverage is fixed, the affection on network lifetime by changing nodes density. When thenumber of nodes is fixed, the affection on network lifetime by changing network coverage.The cluster head of LEACH routing protocol communicates with the base station, if thedistance is far between them, it will bring greater energy loss. This paper takes strategy of hopand multi-hop combination between the cluster head and the base station. It effectivelyreduces energy consumption and ensures the network load balance. The results indicate that,compared with LEACH, the improved LEACH can save and balance the node energyconsumption effectively, delays the first node’s death time, and extends the lifetime ofnetwork.