Study On Hierarchical Energy Efficient Routing Algorithm For Wireless Sensor Networks

With the rapid development of wireless communication,low-power sensor technology and embedded system technology,Wireless Sensor Networks(WSNs)as a full range of information acquisition and processing technology is deeply changing our lives.WSNs is usually composed of a large number of small,low power consumption and multi-functional sensor nodes,each node can transmit datagram and communicate with each other in the network.In practical applications,it is often difficult to replace the battery.Therefore,in the design of routing algorithms for WSNs,the primary goal is to save energy consumption of nodes,prolong the lifetime of the whole network and make it work stably for a long time.In traditional WSNs,all sensor nodes are statically deployed in the sensing area.The data collected by the sensors will be transmitted to the base station or the sink in single-hop or multi-hop manner,which causes sensor nodes close to the sink have more traffic loads and deplete their limited energy quickly.This is the so-called "energy hole" or "hot spot"phenomenon in WSNs.Adding sink mobility into sensor networks can bring in new opportunities to mitigate hot spots problem and improve energy efficiency for WSNs.This thesis mainly makes researches on hierarchical energy-efficient routing algorithm for WSNs in order to balance the energy consumption of nodes and prolong the life cycle of the network.The major work is as follows:1)Relative theories about WSNs and routing algorithms are first reviewed.Then we analyze the characteristics and key technologies of WSNs.Research on the classical uneven cluster-based routing protocol for WSNs.Then,in order to solve the existing shortcomings of EEUC(Energy-Efficient Uneven Clustering)algorithm,such as the election of cluster head node does not consider the residual energy of nodes and the energy expenditure index of inter-cluster routing is not taken into account.We propose an improved algorithm to balance energy consumption and improve the overall performance of the network.2)To further balance the energy consumption of nodes around the sink,a hierarchical energy-efficient routing algorithm based on single mobile sink for WSNs is proposed to mitigate hot spots problem,balance energy consumption and extend the network lifetime,which combines clustering technique,sink mobility and Particle Swarm Optimization algorithm.3)In order to alleviate the formation of hot spot and reduce the delay of the data packet in WSNs.A multiple mobile sinks based routing algorithm for WSNs is proposed.The whole network will be partitioned into different areas,then we define its moving path and select the best location as a data collection point.It can reduce the energy consumption,the network delay and improve the data transmission efficiency.