Study Of Routing Protocol Based On LEACH For Wireless Sensor Networks

Sensor networks, which centered on data, have limited computing capacity, and limited energy supply capacity. Therefore, how to acquire abundance and efficiency characteristic information of sensed object as soon as possible, and transmit to sink node to take into process, is the emphases of presently research. So it is important to study new routing protocols to extend the lifetime of wireless sensor networks.Based on the analysis of existing wireless sensor network routing protocol, this essay especially focuses on the LEACH protocol. We found that there are some problems in cluster-heed selection algorithm and data transmit process after analyzing the performance of LEACH protocol. So this thesis proposes two ameliorated algorithm.(1) In cluster-heed selection algorithm of LEACH, the asymmetry of cluster heeds distribute causes terribly unbalanced load in different cluster and the number of cluster heeds usually depart the optimal range, which cause more energy dissipate. This thesis proposes a cluster heeds selection algorithm based on node located central area. In the new algorithm, the area where cluster heeds locate balance in the wireless sensor networks is considered to optimize the process of the cluster heeds selection and setup a mechanism to ensure the optimal number of cluster heeds. Simulation results show that the new algorithm balances load of cluster heeds, reduces energy dissipate and efficiently prolongs the network lifetime about 30%.(2) In addition, LEACH protocol also has some problems about data transmit time mechanism, which make node's energy usage have great difference among different clusters. As the distance disparities between cluster-heeds and sink, cluster heeds' energy usage have greatly different. This thesis proposes another method to solve the above problem which named cluster-heeds Multi-hops clustering routing algorithm. The algorithm adjusts nodes' data transmit time mechanism and make cluster-heeds transmit data through multi-hops optimal route to base station. Simulation results show that the algorithm improves the performance of LEACH, balances nodes' energy usage, saves transmit energy and further prolongs the network lifetime.