Range Data Correction for Improved Localization

We present a method to correct noisy range data in order to improve localization performance in wireless sensor networks. Mutual ranges between nodes are determined by node positions, and in typical deployments the communication links over which range is measured greatly exceeds the number of unknown node coordinates. We exploit this redundancy to reduce range error. A remarkable feature of our method is that redundancy is exploited strictly in the space of measured ranges, without requiring the construction of a coordinate system. Experimental results in indoor and outdoor environments using our proposed technique show reductions in location error between 35% and 60%.