| 摘要 |
<p>A method and an electronic device for determining the direction of a magnetic field, in which a portable electronic compass device is used to measure three field vectors of the magnetic field the desired number of times. From each measurement, a data point (p1-p6) is formed in a three-dimensional co-ordinate system, for which measured data points a common reference point (C) is calculated. The location of the device is determined relative to the reference point in said co-ordinate system, offset vector V, and the coordinates of the reference point obtained, are compared to the co-ordinates of at least one previous reference point, and the co-ordinate values of the reference point are calibrated, after which the direction of the magnetic field is indicated with the aid of the reference point. The calibration procedure is intended to be able to be reliable yet require low computing power allowing for calibration during use of the device.</p> |
