Indoor Localization with Smartphones: Magnetometer Calibration

Position can be effectively determined through the use of accelerometer, magnetometer and gyroscope sensors available in an inertial measurement unit (IMU). However, the data from the magnetometer plays a major role in estimating the position. The magnetometer is easily affected by external magnetic field during the experiment time. Hard and soft iron effects affect the magnetometer readings. It is necessary to compensate the magnetometer data before estimating the position. This paper proposes a magnetometer calibration algorithm for position estimation. The proposed calibration method has several advantages in terms of elimination of hard and soft iron effects from the magnetometer. The experimental results demonstrate the performance of the proposed calibration algorithm and it gives high position accuracy.