Indoor Positioning Based on Bayesian Filter Using Magnetometer Measurement Difference

A magnetometer is an emerging indoor positioning technique that has a strong advantage in infrastructure requirement. However, due to the cheap magnetometers used in mobile devices, magnetometer based indoor positioning technique suffers from the bias of the magnetometer. In this paper, we propose magnetometer measurement difference (MMD)-based technique for Bayesian filter to mitigate this problem. The proposed technique is much more robust to the bias of magnetometer than the conventional technique when the triaxis of magnetometer in a user device is tilted away from the triaxis of magnetic field map. We provide theoretical analysis and simulation results to compare the performance of the proposed MMD-based technique to the conventional magnetometer-based positioning technique.