Research On Routing Algorithms In Wireless Sensor Networks

Wireless Sensor Network(WSN) is consisted of hundreds of sensor nodes, which transmitted through multiple-hop in the form of self-organization. It collects, fusion processes and transfers the data information of the monitoring region through cooperative communication between the nodes and then send the information to the data monitor. It has broad application prospects in military affairs, national security, environmental monitoring, medical rescue, disaster forecast and etc. However, the energy of sensor node is limited, areas of the sensor network monitoring are usually very complex and the cost is great without battery replacement or battery supply, so balancing network energy and prolonging the running time of the network are very important. Routing protocol is the foundation of the wireless sensor network, so designing efficient routing protocol is the key to the wireless sensor network technology.The thesis introduced the concept, the characteristics, the network structure system and key technologies of wireless sensor network and the thesis mainly focused the application of routing protocol, the design goal of wireless sensor network, and the standard of measuring the performance of routing protocol. Through analyzing and comparing many typical kinds of wireless sensor network routing protocols, the author found that hierarchical routing protocol has obvious advantages in network management, system extensibility, reducing the system cost, improving the network handling capacity, QoS support and other various aspects. LEACH protocol is the first hierarchical routing protocol that is put forward, and is also a benchmark to test other clustering algorithm. In view of the defects in the cluster head election and clustering process of LEACH algorithm, this thesis proposed the improved algorithm LEACH-Improve. In the process of cluster head election, this algorithm fully considers the energy consumption of cluster head nodes, lets the more residual energy nodes which have greater probability to elect cluster heads. In the stage of clustering, it finds a minimum distance of clusters which makes the cluster head distribution more reasonable.In order to evaluate the performance of the improved algorithm, the thesis used the MATLAB software to carry out simulation experiments of LEACH, DEEC algorithm and the improved algorithm LEACH-Improve respectively. And it carried out comparison analysis of the experimental results from the aspects of the selection of cluster head nodes, death nodes, total amount of received data, network energy consumption and load balance. The experimental results showed that the improved algorithm can improve the balance of network load, greatly save the network energy consumption and prolong half of the life circle.