An Energy Balanced Clustering Algorithm Based on LEACH Protocol

The primary objectives of the wireless sensor network routing protocol design are balancing network energy consumption and extending the entire network lifetime. This paper analyses the effectiveness of LEACH protocol in cluster-head selection, and proposes an improved clustering algorithm. This new algorithm takes node’s residual energy and location information into account, optimizes the selection method of the threshold for electing cluster-head, improves optimal cluster-head selection strategy that is normal nodes select the optimal cluster-head based on the cost function. Simulation results show that the improved protocol is better than LEACH in balancing node energy consumption, improving the efficiency of data transmission and prolonging the network life. Introduction Wireless sensor network (WSN) [1] is a self-organized network composed by a large number of micro sensors that are randomly deployed in monitoring regional through wireless communication. With its wide application in military reconnaissance, medical aid, logistics management, environmental monitoring, agriculture and other commercial areas, WSN has become the furthermost technology in the field of communication and computer research [2]. Sensor nodes rely on battery power supply, their communication capability and energy storage capacity are very limited, so how to utilize the energy of nodes efficiently, balance the network energy consumption and extend the network lifetime has become a primary design objective for wireless sensor network. Among the current researches, the clustering routing technology is the most widely influential. Low-Energy Adaptive Clustering Hierarchy (LEACH) is a classical clustering routing in wireless sensor networks [3]. However the cluster-head selection in LEACH protocol is lack of balancing the whole network energy consumption, with the result that low energy nodes run out of energy prematurely and decline the network life. This paper analyses the effectiveness of LEACH protocol in cluster-head selection, and proposes an improved energy balanced clustering algorithm. LEACH Protocol Protocol Description LEACH is the earliest proposed single-hop clustering routing protocol in WSN, it can save network energy greatly compared with the non-cluster routing algorithm. Many other clustering algorithm are proposed based on LEACH, such as TEEN (Threshold Sensitive Energy Efficient Sensor Network Protocol)[4] , PEGASIS(Power Efficient Gathering in Sensor Information Systems)[5] ,HEED(Hybrid Energy-Efficient Distributed Clustering)[6] and so on. In LEACH protocol, all clusters are self-organized, each cluster contains a cluster-head and several non-cluster head nodes, cluster-head node consumes more energy than non-cluster head nodes. With the purpose of balancing network energy consumption and prolonging the network life cycle, it selects cluster head randomly and each node has an equal chance to be cluster-head[7]. The cluster structure update constantly in operation, and one updating process is called a round. The cycle of each round contains two stages: set-up phase and steady-state phase, set-up phase is the establishment phase of the cluster, steady-state phase is the stable data transfer phase. Set-up phase;each node generates a random number between 0 to 1, and compares this number with the threshold value ( ) n T . If the number is less than ( ) n T , the node is selected as a cluster-head, Proceedings of the 2nd International Conference On Systems Engineering and Modeling (ICSEM-13) Published by Atlantis Press, Paris, France. © the authors, 2013 0072 the threshold ( ) n T is set as follow; G n 0 ) 1 mod ( * 1 ) (