Analysis and compensation of background magnetic field error for pedestrian navigation system

The existence of the background magnetic field (BMF) in the environment leads to magnetic sensors' measurement error in pedestrian navigation system (PNS). To solve this problem, this paper designs a magnetic sensor field calibration method applicable for PNS by firstly analyzing the BMF in the environment and building the error model. Then an ellipsoid-restraint-based method is adopted to calibrate the parameters in BMF model. On this basis, we carried out the BMF error calibration experiment and pedestrian trajectory experiment. The results show that the proposed method can effectively compensate the BMF error. Meanwhile, the heading angle calculated by the magnetic sensors can assist to improve the positioning accuracy of PNS. The position error at the end point accounts for 1% of the total walking distance.