METHOD, APPARATUS AND COMPUTER PROGRAM PRODUCT OF ALIASING DISCRIMINATOR FOR ENCODER INTERFACES

摘要

An improved encoder interface system, able to track absolute position athigher encoder velocities without aliasing. The device and related apparatus,method and computer program product can perform this operation without loss ofprecision or accuracy. The improved encoder interface system can predict thephase angle of the signal for each sampling iteration and then measure theangular difference between the predicted phase angle and the actual phaseangle to account for acceleration. The predictive capacity of the systemthereby minimizes the problem of aliasing. As a result of this technique,aliasing will only occur when the acceleration of the object being observedexceeds a certain threshold that, like the Nyquist frequency, is dependent onthe sampling rate of the signal acquisition component. Importantly, in mostapplications, this acceleration limit greatly exceeds any possibleacceleration that the system will undergo.