|dc.description.abstract||Clustering has been widely considered in wireless ad hoc networks as a useful mechanism for solving the scalability problems, improving the stability, increasing the network’s energy efficiency, etc. The idea behind clustering is to group a flat network into a number of clusters. Cluster heads serve as backbones to establish communication routes between sources and destinations in a mobile ad hoc network (MANET). However, election of a Cluster Head (CH) within a local cluster structure is very important in setting up relatively stable cluster structure. This thesis proposes an efficient method to choose cluster heads in wireless ad hoc networks for improving the network stability and energy efficiency. Considering basic requirements in wireless ad hoc network, we propose a novel reliable link lifetime based cluster head election (RLCH) method to determine which nodes are more qualified to serve as cluster heads.
RLCH takes many factors affecting cluster head election into consideration and, unlike the previous approaches proposed in the literature, employs no weight combination when considering the impact of several factors on choosing a CH. In addition, a link lifetime calculation model and a maximum cluster updating interval model are proposed. An adaptive cluster update interval selection process is developed based on an energy threshold approach for prolonging the network lifetime. Four metrics including average number of clusters, cluster update rate, member exchange rate, and energy consumption distribution are evaluated in our simulations. By comparing with other well-known cluster head election algorithms, our simulations indicate that RLCH can achieve better stability, energy saving and longer network lifetime in most cases.||en_US