Improved LEACH Routing Communication Protocol for a Wireless Sensor Network

A WSN (wireless sensor network) consists of thousands of sensor nodes with limited energy, memory, and computation capability. The applications of WSN in some extreme environment make sensor nodes difficult to replace once they use up the resource. Hence, many researchers in this field focus on how to design a property routing protocol to prolong the life span of the network. The classical hierarchical protocols such as LEACH and LEACH-C have better performance in saving the energy consumption. However, the choosing formula neglecting the change of nodes' energy will make the nodes acting as cluster heads too many times die early owing to the consumption of too much energy. Also, the high frequency of reclustering wastes certain amount of energy. In order to make the energy distribute more evenly among different nodes, we improve the tradition equation used for selecting cluster heads with considering the dynamic change of nodes’ energy. Meanwhile, we propose to establish a vice cluster head for each cluster during the communication process, which aims to diminish the energy consumption spent on the reclustering and prolong the time of being in a steady-state phase. Simulations show that our improved protocol performs better than the LEACH and the LEACH-C. 1. Introduction WSN (wireless sensor network) [1] consists of more than hundreds of small sensor nodes which have limited power, memory, and computational capabilities. The application of the WSN involves many fields, such as the military battlefield, forest fire detection, and other extreme environments [2]. In these situations, it is difficult to replace the dead nodes caused by energy’s depletion with new ones to supply energy for the system. Therefore, making sensor nodes working as long as possible is the main method to maximize the lifecycle of the system. Because the energy’s consumption of sensor node mainly originates from the long distance transmission of data along the routing path, an efficient routing path formed by the routing protocol will have a great impact on the energy’s consumption [3]. So how to design an energy-efficient routing protocol becomes the main goal for the wireless sensor network. The conventional wire routing protocol cannot adapt to the wireless sensor network due to the inherent property of WSN. Hence, many protocols have been proposed to satisfy the need of WSN. The cluster idea present in [4, 5] has a significant reflection to the research of WSN routing protocols. It organizes the sensor nodes into different clusters, with a cluster head in each cluster executing