Adaptive Clustering Routing Protocols Research Based On Geographic Location Information In WSN

With the development of science and technology in recent years, WSN (wirelesssensor networks) has been paid more and more attention and widely used in variousfields, especially in the national defense and scientific research.WSN is a kind of self-organizing wireless network built by sensor nodes in theenvironment without infrastructure. Due to the specificity of the wireless sensornetwork, the routing protocol and the localization of the nodes in the network,because of the randomness of the deployment of the most sensor nodes, the locationof the nodes in the network can not be determined in advance, are two key issues ofWSN.Firstly, this paper deeply analyzes the typical hierarchical routing protocolsLEACH which is one of the objects of this study, and discusses the defects of LEACHprotocol. An improved algorithm LEACH-IMP is proposed which improves theperformance of LEACH. There are two main defects in LEACH: the random selectionof cluster heads and redundancy of the communications between clusters. InLEACH-IMP, energy model of nodes is introduced, and then the whole area is dividedinto fixed fields. In each field, select the node with more energy as the cluster head,and then the cluster head adjusts its communication radius. The cluster headcommunicates with the nodes which are possible to join the cluster, so it can reducethe cost of energy. The results of MATLAB simulation show that, distribution ofcluster heads is more balanced, at the same time, network lifetime, throughput andefficiency of energy are significantly improved in LEACH-IMP, compared with theoriginal LEACH algorithm.LEACH assumes that the location of each node is known, but in real network, theposition of nodes is difficult to obtain. Therefore, how to get an accurate localizationis also a hot spot.DV-HOP is a commonly used localization algorithm. Considering the residualsource in the second stage, an improved algorithm DV-HOPSAE is proposed. InDV-HOPSAE algorithm, when we calculate the average distance per a hop, select outthe beacon nodes as a connected sub-network, and then the beacon nodes begin tobroadcast. So we can get the communication path to beacon nodes and its length. Atlast, the average hop distance is obtained using the least square method. Simulation results show that, in the algorithm DV-HOPSAE, the residual of localization is greatlyreduced, and accuracy of positioning is improved to some extent.