Research On Spreading Like Ripples Topology Generation And Topology Automatic Maintenance Algorithm In WSN

Wireless sensor network(WSN)is a kind of distributed and self-organized network,which is distributed large numbers of nodes randomly in the monitoring area.The generation and maintenance of load balanced topology is very important to prolong the life cycle of WSN,so aiming at the characteristics of WSN and restriction and the actual demands of agricultural environmental monitoring,the paper provides Spreading Like Ripples Topology Generation Algorithm(SLR-TG)and Spreading Like Ripples Topology Automic Maintenance Algorithm(SLR-TAM).The main contents of this paper are as follows:First of all,this paper summarizes the related concepts of WSN and topology control technology,and makes a deep research and analysis on the current status and the advanced topology control algorithms in China and abroad.Then I explore the existing defects.Secondly,in view of the found problems and the actual needs of the growth scene of agricultural products,this paper provides the algorithm called SLR-TG.This algorithm uses the Sink node as the center,considering the residual energy,density and distance among its neighbor nodes,then selects the optimal cluster head nodes into the backbone;then according to the selected cluster head to cluster their neighbor nodes;then the selected cluster head node repeat Sink's operations spreading around like ripples;finally,it generates a load balanced topology network quickly.Thirdly,aiming at the hotspot problem because of the cluster head node on the backbone network for data fusion and frequent communication in network and the net hole problem caused by energy depletion or environmental factors lead to node broken,this paper provides a algorithm called SLR-TAM.This algorithm can automatically detect the cluster head node whose energy is lower than the threshold value,and automatically find the best alternative node as a new cluster head to repair the disconnect network and raise the life time.Finally,using simulation software called NS-2 to verify the performance of the algorithm proposed in this paper.Compareing the proposed SLR-TG algorithm and SLR-TAM algorithm to Improved-LEACH algorithm,LEUC algorithm and RCS algorithm,we can draw the following conclusions: the number of cluster heads changes more stable,the topology loads more balanced and total energy costs is more balanced,that improves the life time of network.