Coverage Optimization Research On The Large-scale Wireless Sensor Network

With the smooth progress of the Yangtze River Three Gorges Project and theacceleration of around urbanization construction, the present situation and changes ofecological environment in the Three Gorges Reservoir area has been widespreadattention at home and abroad. Existing monitoring equipments, methods and meanshave been unable to meet the mission requirement. It needs to urgently improve theability of environmental monitoring in the Three Gorges Reservoir Area.As wireless sensor network has the features of low cost, self organization, flexiblecommunication, remote real-time monitoring and so on, it has become a hot issue inenvironmental monitoring. As the application background of the Three GorgesReservoir Area water environment monitoring, on the basis of in depth study theexisting research results, coverage optimization strategy for large-scale wireless sensornetwork for water environmental monitoring in the Three Gorges Reservoir Area hasbeen proposed. Owing to the limitation of node energy in wireless sensor network, wefocused on the coverage optimization strategy and balance of node energy to prolongthe network lifetime.According to the characteristics of large monitoring area and wide distribution inwater environmental monitoring of the Three Gorges reservoir, the coverage feature oflarge-scale wireless sensor networks in water environment monitoring of the ThreeGorges reservoir was researched. Considering the cost of the network, the artificial fishswarm algorithm was applied in the wireless sensor network coverage optimization,which made full use of domestic and foreign research results having been obtained.Because the basic artificial fish swarm algorithm has the defects that convergence isslow in the latter part, solution accuracy is not high and it’s easy to fall into local value,a new algorithm called chaotic artificial fish swarm algorithm with feedback strategyhas been proposed on the basis of artificial fish swarm algorithm. In the new algorithm,the chaos search with ergodicity was introduced into the basic artificial fish swarmalgorithm, and chaos local search based on the search results of artificial fish wasfinished to avoid falling into local value. Meanwhile, feedback strategy was adopted toavoid circuit search in the latter part of the algorithm, which improved the convergencespeed and solution precision.On the basis of the above algorithm, because balance of nodes energy is not considered in traditional coverage optimization strategy, and minimized redundant nodecoverage cannot represent minimized energy consumption of network, we proposed thestrategy of wireless sensor network coverage optimization based on energy management.And the mathematical model was built based on maximized coverage and minimizedenergy consumption of network. The simulation results demonstrate that the proposedstrategy can prolong the network lifetime and save network energy under the premise ofensuring coverage.