Research On Data Collection With Mobile Sink Based On Balance Of Energy Consumption In Wireless Sensor Networks

In Wireless Sensor Networks,how to efficiently use sensor node's energy to prolong network lifetime is still one of the key issues in this field.Because the energy of sensor nodes is limited and will not be supplemented again,the nodes near the base station will be unable to transmit the collected data to the base station owing to the large load.In order to alleviate the "hot spots" problem of the nodes around the base station in a static network,this thesis proposes data collection strategy based on single Sink and multi-Sink respectively in Wireless Sensor Networks.(1)A type of energy-balance tree based data collection strategy in sensor networks with a mobile SinkIn order to enhance the sensing efficiency of Wireless Sensor Networks,a type of energy-balance tree based data collection strategy with a mobile Sink(ETDC)is designed and implemented.Firstly,to optimize data uploading path and reduce energy consumption on communication,an energy balanced tree is constructed.Then,this tree is further divided into several sub-trees with similar scale and less energy consumption for data gathering.The root nodes of each data collection tree are regarded as the traversal nodes and the moving trajectory of Sink is obtained by fitting the location of these traversal nodes.Finally,in order to further reduce the communication energy consumption and delay,the roles of some traversal nodes and relay nodes are adjusted.Simulation results show that the algorithm has some advantages in balancing energy consumption and prolonging network lifetime.(2)Data gathering scheme based on grids in Wireless Sensor Network with mobile SinksTo prolong the lifetime of Wireless Sensor Network and reduce time delay on data collection,a type of data gathering scheme based on grid with mobile Sinks is also proposed(GBDG).The network is firstly divided into several rectangular grids with uniform size,whose center just is stay point.The number of mobile Sinks is decided by the network scale as well as the total number of grids.Next,the data collection tree based on minimum single-hop distance is constructed in each grid to achieve low power consumption on data uploading.In addition,the grid priority depends on the cache status of each node in this grid.Finally,mobile Sinks move from one stay point to another at a constant speed,and the traversal order can be determined according to the neighbor grids priority to realize the fairness in data collection.Simulation results show that this strategy not only reduces the average energy consumption of whole network nodes or prolongs the network lifetime effectively,but also ensures a higher data transmission success rate.Furthermore,the length of the moving path is greatly shortened due to the multi-Sink's cooperation,which effectively reduces the end to end delay in data collection.