The Research Of Hierarchical Data Collection Algorithm For Wireless Sensor Networks

In recent years, wireless sensor network is developing rapidly because the wireless communication has become increasingly mature. Wireless sensor network is composed of a large number of sensor nodes.These sensor nodes collect data from monitor environment, make data fusion, and then transmit to the observer. In the wireless sensor network, sensor nodes colloect data after the network topology structure built up. Reducing the network energy consumption and network load is an importantquestion to the wireless sensor network.A new algorithm which called Hierarchical Data Collection algorithm(HDCM) is proposed in this thesis.In the HDCM, the mediation node is introduced between the sink node and sensor node. Firstly,all sensor nodes in the area are divided into groups. In each group, the head node is seleted by the residual energy strategy. Head node is responsible for accepting member report which produced by member nodes.Then leader report is generated by data fusion argorithm. The mediation nodewhich is closest to the sink is selected as agent. Adopting breadth-first algorithm, a minimum spanning tree can be built inwhich the agent is the root, head nodes are the leaves, and other mediation nodes are thebranches.The root is responsiblefor receiving leader reports from the head nodes and query from the sink node, then form the aggregator packages and sent to the sink node directly. Simulation results show that HDCM is able to achieve a certain degree of network load balance and is more efficient in sending data, its energy consumption is relativelysmall.Thus the lifetime of wireless sensor network is extended.