Fuzzy Positioning Algorithm Based on Wireless Sensor Networks

Aiming at the shortages of positioning technology in Wireless Sensor Networks (WSNs), a fuzzy positioning algorithm based on WSNs is proposed. Line segments connecting anchor nodes intersect and the algorithm regards intersection points as sample points which should assist with the positioning and improve positioning precision when there are fewer anchor nodes. The positional relationship of the sample point and unknown node is described using grade of membership functions of fuzzy theory, and then the sample nodes whose grade of membership are larger will be chosen to calculate the position coordinates by weighted average. The algorithm reduces the influences to a certain extent which are caused by errors of Received Signal Strength Indication (RSSI) measure. Therefore the algorithm improves the accuracy of positioning and avoids high computational complexity and the requirement of more anchor nodes. Simulation results indicate that the algorithm has better performance and practicability.