Hierarchical routing optimization in wireless sensor networks [document

Abstract

Wireless Sensor Networks (WSNs) are composed of hundreds of tiny sensor nodes with limited resources communicating with each other to monitor the environment. Sensor nodes are usually powered by a battery. Consequently, energy efficiency is critical for the lifetime of the Wireless Sensor Network. Routing protocols are the most important issue for WSNs. LEACH (Low Energy Adaptive Clustering Hierarchy) is one of the first hierarchical routing algorithms for WSNs. LEACH uses Cluster Heads (CHs) to mediate data transmission. This thesis contains a new formula for the Cluster Head selection process and two new routing protocols. The new formula introduces the residual energy of the node in the CH selection process. The first improved protocol uses a Vice-Cluster head (VCH) for each cluster to replace the CH when it dies. The second new protocol is an improved LEACH-C protocol in which, the Sink uses a Consumption Model for each Sensor Node (CMSN) to estimate the amount of energy needed for the next rounds ,so sensor nodes don’t have to send the value of current energy to the base station at the beginning of each round like it does in LEACH-C. Simulation results show that these improvements extended the network lifetime compared to previous works.