Patent ID: 7606676
Filing Date: 2009-10-20
Classification: G01C

Abstract:
1. An azimuth data computing method comprising: inputting a signal from a geomagnetic sensor to measure a magnetic field which may be a mixture of a geomagnetic field and other magnetic field causing an offset, thereby providing measurement data of the magnetic field, which is represented by a set of coordinate components corresponding to a set of different axes of a given coordinates space; storing the measurement data; calculating an offset value of the offset based on a plurality of the stored measurement data; when the offset value is greater than a predetermined reference value, returning to the step of storing the measurement data while removing the offset value from each measurement data successively measured from the inputted signal; when the offset value is smaller than the predetermined reference value, updating a previous offset value according to the offset value; and correcting the measurement data which is provided after the previous offset value has been updated, according to the updated offset value and computing azimuth data according to the corrected measurement data.