Research On Coverage Control For Wireless Sensor Networks

Wireless sensor networks are used in a wider range,such as in the fields of military,security,surveillance,ecological environment monitoring,medical and health.Coverage control can optimize the space resources,serve to the environmental complete awareness,and be effective to information transmission.In this paper,the coverage control of WSNs is the focus of research,and some problems of k-coverage control are discussed.At first,the characteristics of wireless sensor networks are considered and an overview of coverage control is presented.On this basis,a coverage control algorithm based on the probability sensing model is proposed.Then the "coverage hole" problem resulted in uneven coverage is considered,and the method of the "virtual force" based on mobile nodes is presented.The main works are as follows:Firstly,this paper gives a comprehensive analysis of the characteristics of wireless sensor networks,analyzes the current coverage control research of wireless sensor network,introduces the classification of a typical wireless sensor networks coverage control algorithms,and points out the issues of coverage control of wireless sensor network,of which the service quality in single coverage only depends on the monitoring results of a single node.A node failure may lead to the network failure,so single coverage is difficult to fulfill the needs of the applications.According to the problems mentioned about,the paper introduces some typical types of k-coverage control algorithms and discusses the characteristics of each algorithm and the problems in current researches.Secondly,a novel k-coverage control algorithm based on the probability sensing model is presented.Any point in the target area sensed by a sensor is given a value based on the sensing capability.In the algorithm a sensor compares its residual energy with the neighborhood.The sensor and its neighborhood cooperate to construct k working covers that provide probabilistic coverage for the whole target region.The algorithm activates less number of nodes,prolongs the lifetime of the network.The theoretical analyses prove that the algorithm has lower data transmission costs and less time wasting.Thirdly,a mobile node based method is presented to provide the whole coverage. The method combines a dynamic programming algorithm,and a heuristic virtual forces algorithm,which provides a good basis for connectivity and attracts mobile sensors move there.In this method a few mobile sensors are added into an existing sensor network to improve the connectivity and coverage,which makes up the hole of coverage caused by random deployment or the uneven energy consume.In the end,the two presented algorithms are implemented on NS2,and the relative performances are analyzed through contrasts.Simulation results prove that the algorithms are effective.