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

摘要

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