Abstract
This paper describes a state space model for estimating the location of a mobile wireless client based on sensor data fusion. Data pertaining to the physical position of personal electronic devices or mobile robots are important for information services and robotic applications. We use the strength of signals received by wireless LAN access points to locate mobile clients in multistory buildings. We also use the acceleration of the mobile client as sensor data. The output of an accelerometer is prone to uncertainty; we use a probabilistic model of the location estimated by wireless LAN signals and the acceleration acquired by a sensor to create an observation model. In addition, a simplified measurement method is proposed for use by a fingerprinting-type estimation system based on human footsteps. Experimental results show the feasibility of the proposed method.