Research On Geographic Routing Protocol In Wireless Sensor Network

In wireless sensor networks, routing protocol is a key technology which determines the networks performance. Geographic routing protocol is mainly studied in this paper. After the analysis of GPSR which is a typical routing protocol, it can be known that there are some problems:(1) The node which is nearest from the destination node is selected as the next hop node in GPSR. This selection strategy doesn't consider the energy efficiency, so its energy consumption is relatively high;(2) A data packet will be forwarded along the communication void boundary by the right-hand rule when the data packet encounters the boundary. The energy of nodes on the boundary is exhausted because of excessive consumption, and it will cause the void's diffusion. Meanwhile, it will lead to data collision when multiple communication sessions share the same boundary of communication void simultaneously and make the success rate of data packet forwarding low. Finally,In order to solve the first problem, this paper analyses the energy consumption model and gives a formula which is used to calculate the optimum transmission range. According to the formula, a new selection strategy of next hop node is devised and an improved protocol is proposed. Finally, the simulation experiments verify its effectiveness.For the second problem, a ellipse model has been used in this paper. it uses the ellipse tangent to locate the next hop forwarding data packets position and gives detailed calculation formulas. At last simulation experiments are conducted.The simulation results show that the improved protocols and algorithms superior to the original protocols and algorithms in some ways.