A Study On Energy-Balanced Clustering Routing Protocol In Wireless Sensor Networks

Wireless sensor network is composed of a large number of sensor nodes with low-cost and small size, and it is self-organization. One of the most restrictive factors on the network lifetime is the limited energy resources of the sensor nodes. Routing protocol based on clustering techniques can increase utilization of energy and prolong the lifetime of wireless sensor networks. Thus, in order to achieve high energy efficiency and assure long network lifetime, clustering routing protocol becomes a worth research.The elegant clustering routing protocol LEACH randomly selects a few nodes as cluster heads, and balances the energy dissipation of nodes in the networks by rotating the cluster head role uniformly and periodically among the nodes. Compared to the flat routing protocol, LEACH can increase utilization of energy and prolong the network lifetime. But the actual energy consumption of network is far from equilibrium in LEACH, which could affect the network lifetime significantly.To solve the problem of unbalanced energy consumption of nodes in traditional clustering routing protocol of LEACH, this paper proposes Cluster Head Multiply-Selection Energy-Balanced Routing Protocol(CMSEB) and Cluster Head Multiply-Selection Energy-Balanced Multi-Hop Routing Protocol(CMSEB-MH), including cluster head multiply-selection strategy, new cluster head selection algorithm and cluster member assignment algorithm, as well as heuristic multi-hop inter-cluster communication mechanism, to balance network energy consumption and prolong network lifetime. This paper completes the following aspects of work:(1) This paper studies the load imbalance of cluster head caused by the unstable number of cluster heads and the uneven distribution of cluster heads in LEACH. We design a cluster head multiply-selection strategy to achieve cluster head uniform distribution and make the number of cluster heads in each round to maintain a certain degree of stability. After cluster head pre-selection, the strategy increase or decrease the number of cluster heads in the region based on the judgment of CH-sparse region and CH-intensive region, so as to evenly distribute the cluster heads. At the same time, this paper studies the unbalanced energy dissipation of nodes caused by the independence of the nodes’ respective energy consumption. We take the residual energy of nodes into account, and design a new cluster head selection algorithm and a new cluster member assignment algorithm to solve the problem. We control the load of nodes according to their different residual energy (i.e. whether to be a cluster head and the cluster size), so as to achieve the target of energy balance. Based on the above strategy and algorithms, this paper proposes Cluster Head Multiply-Selection Energy-Balanced Routing Protocol(CMSEB). Then this paper analyzes the complexity of CMSEB, and proves the message complexity is O(N). Finally, through a series of experiments, we compare and analyze CMSEB with LEACH and HEED in performance. The results show that CMSEB is better in cluster head stability, network energy consumption balance and network lifetime extension, compared with LEACH and HEED, and outperforms LEACH30%in prolonging the network lifetime.(2) To solve the problem of excessive and unbalanced energy consumption caused by single-hop inter-cluster communication, this paper deeply analyzes the causes and impact of the problem on the whole network. We introduce the multi-hop inter-cluster communication mechanism. Each cluster head computes the minimum energy consumption forwarding path by a heuristic way, then selects the next hop respectively based on the computing. By this distributed computing of cluster heads, we can generate the multi-hop routing of the whole network. And, through setting the direct communication region of base station, we can alleviate the hot-spots problem and delay problem of multi-hop mechanism. Finally, through a series of experiments, we compare and analyze CMSEB-MH with LEACH and CMSEB in performance. The results show that CMSEB-MH is better in network energy consumption balance and network lifetime extension, compared with LEACH and CMSEB, and outperforms LEACH45%, CMSEB12%in prolonging the network lifetime.In wireless sensor network, under the premise of limited node energy, the research of increasing the energy consumption balance and prolonging the network lifetime is very important. And it can make a significance to promote the development of wireless sensor network technology.