Three-dimensional Accurate Positioning Algorithm based on Wireless Sensor Networks

Three-dimensional accurate positioning algorithm, using RSSI-based (Received Signal Strength Indication) positioning method, which constructs an attenuation model of wireless signal between beacon node and unknown node in three-dimensional space, and compensates for the loss of wireless signal on the basis of their material, thickness and other factors when there are obstacles or walls being in the process of signal transmission. Meanwhile, the error revision algorithm is used to improve the positioning accuracy. The update interval and transmitting power can be changed adaptively according to the movement speed of unknown node and the distance to beacon node, so that the wireless node's life cycle will be extended greatly. Moreover, it will be able to complete positioning even a few beacon nodes fail in some cases. Furthermore, the location information provides a premise and basis for the research on geographic routing algorithm.