Research On Clustering Hierarchy Tree Routing Algorithm Based On Leach

Wireless sensor network is a self-organizing and multi-hop network system that consists of a large number of sensor nodes organized by wireless communication. It can real-time monitor, find and collect information within monitoring coverage. And it has a great future that seemed as one of the most promising technologies in the 21st century. Routing protocol is the key of wireless sensor network and today it is the hot area at home and abroad.Wireless sensor network is different from traditional wireless network , people have done a lot of researches for the routing protocol of wireless sensor network. The paper analyzed the existing wireless sensor network routing protocol and investigate their features and performance. According to the key factor that should be considered when we design wireless sensor network routing protocol, the paper proposed a new routing protocol named Clustering Hierarchy Tree routing algorithm based on LEACH, which is called CHT_LEACH for short, the routing algorithm made some improvement for LEACH protocol at formative stage of cluster and phase of inter-cluster communication.At cluster formation stage, the paper presented the concepts of candidate cluster head, final cluster head, for the asymmetrical distribution of cluster heads and not having taken into account the residual energy of cluster heads. The cluster heads selected by the cluster head formatting mechanism of LEACH protocol are candidate cluster heads, in the range of cluster radius R, the candidate cluster head that had the largest remaining energy became a final cluster head, and the final cluster head is responsible for data integration and forward. Through selecting a final cluster head from candidate cluster heads , this algorithm not only avoided the problem of two or more cluster heads together, but also took into account the residual energy of cluster head compared to LEACH protocol. By this way, the residual larger energy of cluster heads evenly distributed across the network area, thus the algorithm avoided redundant data transmission and premature deaths of cluster head. At inter-cluster communication phase, for the cluster head in the form of a single-hop communicating with sink in LEACH protocol, the paper presented a method-each cluster head formatted a hierarchical tree that took the base station as its root: each cluster head selected its parent node with the distance to the base station and residual energy, integrated the data of cluster members and child nodes and then sent to its parent node. Followed by analogy, until the data arrived the base station. This routing shorted the data transmission distance of cluster heads and greatly saved its energy, thus prolonging the life time of the wireless sensor network.Through theoretical analysis and OMNET++ simulation, the paper verified that CHT_LEACH algorithm had greatly improved at node energy consumption, node residual energy and energy balance compared to LEACH protocol.