Location Tracking in Wireless Local Area Networks with Adaptive Radio MAPS

This paper proposes a dynamic MMSE estimator for tracking mobile users in indoor wireless local area networks (WLAN) based on received signal strength (RSS). The method uses a training-based static estimate obtained by an adaptive kernel density estimator as the input into a Kalman Filter. Predictions from the filter are used during the next iteration to adaptively select a subset of training data, contained in a radio map, for the static estimator. Experimental results show that the combination of the Kalman filter and the adaptive radio map technique results in nearly 0.5 m (20%) improvement in root mean square location accuracy when compared to static localization