Research On Clustering Route Of Heterogeneous Wireless Sensor Networks

The wireless sensor networks (WSN) are a special kind of ad-hoc networks that consist of a lot of sensor nodes whose calculation, communications, storage ability and power are so limited. The wireless sensor networks have been extensively applied to military, environment monitoring, industry, health and so on, which have become a research hotspot.The network coverage and energy consumption are primary problems of WSN. The energy consumption determines the network lifetime, and the QOS of WSN depends on the network coverage. The density control is a right way to reduce energy consumption and prolong the network lifetime. This dissertation investigates the clustering routing algorithms of the heterogeneous WSN to save the energy and maintain the network coverage. The main contributions of this dissertation are as follows:(1) A new distributed clustering scheme CDEE (Clustering Algorithm based on Distance and Energy-Efficient) is proposed for multilevel energy heterogeneous WSN. In this scheme, cluster-heads are selected based on not only the distances between the nodes and sinks, but also the ratio between the node residual energy and the average network energy. The nodes, which have the more residual energy and the closer distance to sink, have the more chances to become the cluster-heads. The simulation results show that CDEE can not only reduce and balance the energy consumption, but also increase the stability period and lifetime of the network.(2) A clustering routing algorithm CRCC(Clustering Route Based on k-Coverage and Connectivity) to maintain k-coverage and connectivity is presented for heterogeneous WSN with high node density. In heterogeneous WSN, too much active nodes are needed to k-cover the monitored region when the sense ranges of some nodes are so narrow that the node density must be very high to meet the monitor demand. To avoid the above situation, CRCC selects rm 'in(the radius of the largest enclosed sense disks) according toψ(ψis the expected ration between the amount of the nodes whose radiuses of the largest enclosed sense disks smaller than the set value and the amount of all nodes in WSN). Simulation results shows that CRCC needs less active nodes than other existing k-coverage protocols to k-cover the monitored region. So CRCC can reduce the energy consumption and prolong the WSN lifetime.