Patent ID: 7620514

Claim:
A method for correcting a sensor system selected from the group consisting of an angle-measuring sensor system, a distance-measuring sensor system, and an angle-and a distance-measuring sensor system comprising the steps of evaluating sinusoidal and cosinusoidal measurement signals (x i y i ) obtained by scanning a moved measurement object in a magnetic field; correcting errors of the measurement signals (x i y i ) selected from the group consisting of angle errors, phase errors, and angle and phase errors providing for the correcting the sensor system a compensation process and a subsequent correction process; in the compensation process, providing offset values (x o , y 0 ) from a specified number (N of j=1. . . N) of pairs of measured values (x i , y i ) obtained by rotating a magnetic field, for the sinusoidal and cosinusoidal measurement signals (x i y i ) and correction parameters (m 1 , m 2 ) by applying a least square of errors method and solving a linear system of equations; determining a corrected pair of measured values (x i ′ y i ′) from each pair of the measured values (x i y i ) in the correction process, whereby determining the corrected pair of the measured values (x i ′ y i ′) in the correction process based on the relationship x i ′=x i −x 0 and y i ′=m 1 ·x i ′+m 2 ( y i −y 0 ), whereby determining the pair of measured values (x i y i ) in the compensation process located on ellipses and satisfying the following equation: f ( x, y )=w 1 ·x 2 +2· w 2 ·x·y+w 3 ·y 2 +2· w 4 ·x+ 2· w 5 ·y± 1, whereby determining parameters of elipses (w 1 . . .w 5 ) using the least square of errors (g) method, with g = ∑ i = 1 N ⁢ f ⁡ ( x i , y i ) 2 = min ; and determining with a processor an angle (α) to be measured from particular corrected pairs of the measured values (x i ′ y i ′) using an algorithm and thereby providing the correction of the sensor system.