| 摘要 |
A system and method for real time calibration of a quadrature encoder. Errors from sources such as signal offsets, amplitude mismatches and phase errors are addressed. In one embodiment, the errors are addressed by determining and applying a dynamic operational set of calibration parameters. The process for determining the operational calibration parameters involves minimizing a variation metric that indicates the variations of the magnitudes of a set of corrected vectors Ci''. The corrected vectors Ci'' are defined by using the calibration parameters to provide corrected vector components (Ati'', Bti'') that correspond to a current operational set of quadrature signal samples comprising at least four respective quadrature signal samples (Ati, Bti) having spatial phase angles thetati that are distributed over a significant portion of 360 degrees. For well chosen calibration parameters, the resulting corrected vectors define a well-centered circle and the variation metric is minimized.
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