The Research Of Wireless Sensor Network Energy-Saving Routing Algorithm Based On Geographical Information

Wireless sensor network comprises large number of sensor nodes densely located in an area for the purpose of collecting, processing and forwarding information. A key point in wireless sensor network is that sensor nodes have limited battery resources and are non-replenished in some applications. Consequently, energy-efficiency is an important consideration for the routing algorithm as it affects the network lifetime.The thesis analyzes wireless sensor network routing algorithm, including flooding, hierarchical, data-centric and geographical information. Geographic information routing algorithm has such features marked by easily implementation, effectively-utilization of energy and dependence, currently it has become the primary research area. Based on analyzing GPSR and GEAR algorithm, this thesis puts forward Geographical and Delaying Network Division Routing (GDDR) algorithm and Geographical and Energy Efficient Routing (GEER) algorithm.1) GDDR algorithm:In GDDR algorithm source node sends the RTS message, destination node will feedback FM message to source node along the original path after receiving the RTS message, or the node which receives the RTS message encounters communication hole, it will also feedback FM message to source node along the original path. Source node decides to use greedy forwarding or perimeter forwarding according to all FM message. Meanwhile, the source node according to the path field of all FM message chooses the forwarding path that its node number is the least.2) GEER algorithm:Considering the energy consumption of idle state node can not be ignored, this thesis puts forward GEER algorithm which combines node’s geographical information, energy and state. In GEER algorithm every node keeps and maintains a neighbor nodes table. Anytime when a node selects the next node to relay the packet, the node chooses its neighbor node according to a certain probability P, the greater the weights, the greater the probability of being selected. Local nodes fomat a stack according to the mutual distance, when a node of the stack sends data, and the remaining nodes are switched the sleeping state. This thesis implements GDDR algorithm and GEER algorithm in NS-2. Simulation shows that GDDR algorithm delays network division. GEER algorithm reduces the energy loss and prolongs the network lifetime.