Research On The Improved Scheme Of SEP Protocol Based On Cluster Head Election And Multi-hop

Wireless sensor networks are being used widely in many fields.In some practical applications,energy consumption is the key problem that restricts its performance.Therefore,how to make full use of the limited energy and extend the lifetime of the network is a major problem in the design of wireless sensor networks.In this paper,the research goal is to balance the energy consumption and extend the lifetime of wireless sensor networks.Based on the Stable Election Protocol(SEP),some new solutions are proposed to prolong the survival time of nodes in the network.The main work of this paper includes:(1)The structure and characteristics of wireless sensor networks are discussed.The design factors of routing protocols and some typical routing protocols are analyzed.This paper focuses on the model and process of Stable Election Protocol.The shortcomings of SEP in cluster head election and data transmission stage are analyzed.Combined with other related research results,several improvement methods of SEP to extend the lifetime of network are researched.(2)In order to solve the problem that too few factors are considered in cluster head election,a new improved protocol N-SEP is proposed.N-SEP considers the influence of the residual energy and location information of the node and its neighbor nodes on the cluster head election.Firstly,the appropriate coverage radius is selected to determine the selection range of neighbor nodes.Secondly,a comprehensive factor is introduced to weight the cluster head election probability of nodes,so that the nodes with higher residual energy,ideal deployment location and lower intra-cluster communication cost will have higher election probability.Finally,in the threshold formula,low energy nodes are restricted from participating in cluster head election.The simulation results show that the stability period of N-SEP protocol is extended obviously,and the network performance is also improved.(3)In order to solve the problem of excessive energy consumption of cluster head node,this paper proposes an improved protocol MN-SEP on the basis of N-SEP.MN-SEP adopts multi-hop transmission between cluster head nodes.The comprehensive evaluation function is designed according to the residual energy and the direct communication distance to the sink node.Within a specific area,the value of the evaluation function of candidate nodes is compared,and the candidate node with the largest value of the function is selected as the node of the next hop.The simulation results show that the number of rounds in which the first dead node appears is significantly prolonged,and the overall energy consumption is also improved.