Research Of Data Collection Technology With Balanced Energy Consumption For Wireless Sensor Network

Recently,wireless sensor network(WSN)technology has been a hot research topic and widely applied.As there is no need to build network infrastructure for WSN in advance,WSN enable quick networking and environmental data collection.Currently,WSN has been widely applied in military and civilian fields.The WSN clustering routing protocol has the characteristics of good scalability and energy efficiency,which is suitable for large WSN environment.But in the WSN clustering routing protocol,the cluster head's energy consumption is large,whose reliability and stability has a huge impact on performance of WSN.Meanwhile,the nodes near a base station need forward data from nodes far away from the base station.Imbalanced energy consumption results in exit of nodes and shortened network life cycle.Therefore,the idea of using a mobile base station to actively collect data of sensor nodes to yield good results has been presented by researchers.Therefore,this dissertation mainly focuses on clustering routing protocol with balanced energy consumption and WSN clustering data collection protocol based on mobile base station under constrained tour length.The main work of the thesis is listed as follows:1.Based on the LEACH protocol,a WSN clustering routing protocol based on energy distribution within node's neighborhood is proposed.Firstly,a threshold for cluster head selection is designed based on the neighborhood node density and relative deviation of form that of its neighbors.Secondly,candidate cluster heads detects whether it is located in an isolated area.If so,a by-election of cluster heads is presented.In the end,cluster heads broadcast joining messages to attract neighboring nodes to join its cluster.So energy consumption caused by global broadcast is avoided.Simulation results show that the proposed algorithm optimizes the cluster head distribution,balances the energy consumption and extends the network life cycle.2.A WSN clustering data collection protocol based on mobile base station is proposed.Firstly,cluster heads are generated based on the original clustering routing protocol such as LEACH.Secondly,according to distance between each cluster head and starting point of a base station,cluster heads and a mobile base station will be organized into a minimum spanning tree.Then determine the preorder traversal sequence of cluster heads based on minimum spanning tree with approximate ratio to optimal traverse sequence less than 2.Based on the order of cluster heads traversed by a mobile base station,we design a load balancing mechanism for nodes to join a cluster which considers residual energy of cluster heads to assign capacity quota for each cluster.As a result,clusters with reasonable size are formed.Finally,a mobile base station collects data from each cluster head in sequence.Simulation results show that the presented clustering data collection protocol based on mobile base station can extend network life cycle than the original clustering protocol.3.For delay intolerable applications,sensor nodes' data must be submitted to a mobile base stations within a specified time limit.A WSN clustering data collection protocol based on mobile base station under constrained tour length is presented.The above WSN clustering data collection protocol based on mobile base station is extended under constrained tour length.As not all cluster heads will be directly visited by a mobile base station under constrained tour length,those cluster heads directly visited by a mobile base station are set as the first level cluster heads,while other cluster heads are set as the secondary level cluster heads.The secondary level cluster heads forward data to a nearest first level cluster head.Thus a second-level structure based on clustering is formed.Simulation results show that the extended data collection protocol can also expand the network life cycle under constrained tour length when compared with the original clustering protocol.