Study And Improvement Based On LEACH Protocol In Wireless Sensor Networks

Wireless sensor network is an application-oriented network system which is fairy close to the physical world, and it is widely used in military, agriculture, medical treatment, transportation and almost every aspect of people’s daily life in nowadays. Because wireless sensor network is usually deployed in the relatively harsh environment, and the power of each sensor node is very limited, the number of sensors is very large, so that replacing or recharging the battery for each node is not realistic. The traditional wireless routing protocols can not be directly used in WSNs. This characteristic also becomes a bottleneck factor that restricts wide application of wireless sensor network.LEACH algorithm is a classical hierarchy routing protocols, which can effectively balance energy consumption of network. Comparing to common flat routing protocols, LEACH algorithm can prolong the life of network about15%. LEACH algorithm also becomes the foundation of many hierarchy routing protocols. Thus, researches on LEACH are of great practical significance.The work of this paper can be summarized as the following aspects:First, this paper has an explicit analysis of architecture and protocol stack structure of wireless sensor network, then a further analysis on LEACH algorithm is made by analyzing its working process and the key technology.Second, through these analyses, some shortcomings in LEACH protocol are pointed out, and improvement are proposed about the selection of cluster head in LEACH. During the cluster head selection process, the residual energy and distance to base station of nodes are considered. And the assist node was added to balance the power consumption of cluster head. Based on this improvement, energy consumption of network and the life of network are expected better performance comparing to the original LEACH algorithm.Finally, we use NS2to simulate the operation of networks using LEACH and the improved algorithm, and through the comparison of the simulation result.such as number of nodes alive, energy consumption of network, data collection of base station, we found the improved algorithm can balance the energy consumption better than original LEACH protocol.