Study On Energy Efficient Routing Algorithm Based On Mobile Sink In Wireless Sensor Networks

Cloud empowered computing and techniques are becoming more and more popular in recent years.Wireless sensor networks(WSNs)can be supported from bottom layer to the upper application layer by cloud computing techniques.Once the wireless sensor network is deployed to the target area,it can be real-time perception of the target area that is due to the nodes in the network can cooperate with each other.WSNs have various applications in many fields such as military,agriculture and health care etc.Because of the limiting of battery capacity can't be replaced,so that the efficient use of node energy has become the focus and difficulty in the design of routing protocols.In traditional routing scenarios,the sensor nodes transmit information to the sink node in a multi-hop manner.However,as the sink node is fixed,some sensor nodes near the sink need relay more date than others far away from the sink.This phenomenon is called as "energy hole".The sensor nodes near the sink node will consume more energy and be dead too early,the corresponding sensor nodes are also referred to as "hot nodes".Adopting sink mobility has been exploited in recent years to prolong the lifetime of wireless sensor networks.Contrary to wireless sensor networks with a static sink,the mobile sink-based approaches can alleviate hot spot issues and balance the energy consumption among sensor nodes.This thesis mainly makes researches on energy efficient routing algorithms based on mobile sink for wireless sensor networks to prolong the network lifetime.The main work is as follow:1.Relative characteristics and challenges about wireless sensor network and routing algorithms based on mobile sink are firstly reviewed.Routing protocols can be divided into three categories and has carried on the comparative analysis according to the characteristic of the mobile sink.The disadvantages of MECA algorithm and PEGASIS algorithm had analyzed.Then we proposed an improved algorithm aiming at these two problems.2.This thesis proposed an energy efficient dynamic routing adjust algorithm based on mobile sink.By setting some communication rules that manage routes reconstruction process,there will not be a phenomenon of the whole network reconfiguration with the mobility of the sink node.The cluster head rotation mechanism alleviated the hotspot problem efficiently,and also avoided frequent cluster head selection and intra cluster routing reconstruction.3.This thesis combines clustering algorithm,ant colony algorithm and mobile sink to further improve the overall performance of the network.The distance heuristic factor is considered in order to enhance the global search ability by considering the distance between the cluster heads.Then,mobile sink finds an optimal sink mobility trajectory by the improved ACO algorithm to communicate with all cluster heads.