Distributed Localization for Wireless Sensor Networks Using LFM Waves

A novel distributed localization method for wireless sensor networks (WSN) is proposed in this paper. Linear frequency modulation (LFM) waves are emitted from two anchors simultaneously to create an interference field. Through the frequency measurement of local RSSI (Received Signal Strength Indication) signal, the TDoA (Time-Difference-of-Arrival) is estimated independently at each sensor to detect range difference from the sensor to the two anchors, by which the position can be determined. Furthermore, an extended method applied to mobile sensors is also presented. The proposed method only relies on radio transceivers and requires no time synchronization for sensors. Simulations results demonstrate the effectiveness of our method.