SIGNAL PROCESSING METHOD FOR USE WITH AN OPTICAL NAVIGATION SYSTEM

摘要

A signal processor and method are provided for detecting movement of a surface relative to an optical sensor having an array of photosensitive elements. Generally, the method involves: (i) sampling each of a number (M) of phase signals from the photosensitive elements, each of the M signals having a magnitude and including a tracking signal at a frequency being tracked and a background signal at other frequencies that offset the tracking signal (402); (ii) eliminating the offset to the tracking signal due to the background signal to generate M non-offset phase signals (404); (iii) adjusting phase angles of the non-offset phase signals to generate M weighted phase signals (406); and (iv) combining each of the M weighted phase signals to generate an average weighted phase having a phase angle (408), that when tracked over time indicates a direction and velocity of the movement.