Research On Node Scheduling Algorithm For Heterogeneous Wireless Multimedia Sensor Networks

Wireless sensor networks consist of densely deployed and energy-limited sensor nodes. How toextend the lifetime of wireless sensor networks without affecting the network performance andservice quality has become the key point. Recently studies have shown that node schedulingalgorithms can solve the energy consumption problem effectively, which can extend the lifetimeand ensure service quality simultaneously.Recently, many node scheduling algorithms have been proposed, however, works onheterogeneous network are still small. Based on the analysis of current node scheduling algorithms,this thesis proposes two scheduling algorithms:Grid-Based Node Scheduling algorithm(GBNS) andNeighbour Distance-Based node Scheduling algorithm(NDBS). GBNS classifies the nodes based onminimal covering set, and builts a model of maximal set number of nodes. It accomplishes thescheduling of groups by classification of heterogeneous sensor nodes and certain schedulingstrategy. NDBS categorizes all nodes into three kinds by the distance between neighbor nodes andsensor nodes. It builts a mathematical model to describe the relationship among the coverage rate ofperception scope, number of neighbor nodes and ratio of radius. Based on the mathematical model,this thesis establishes a redundancy evaluation to turn off redundant nodes. Theoretical analysis andsimulation results show that, both two node scheduling algorithms can effectively extend thelifetime of network.