The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 16, 2010
Filed:
Jun. 23, 2008
Michael Eugene Jones, West Linn, OR (US);
David Douglas Martenson, Oregon City, OR (US);
Michael Eugene Jones, West Linn, OR (US);
David Douglas Martenson, Oregon City, OR (US);
Xerox Corporation, Norwalk, CT (US);
Abstract
An encoder position signal processing system comprises an analog encoder reader and a codewheel. The codewheel possesses an optical track that modulates the quadrature encoder signal amplitude in order to generate an amplitude change (home pulse) once per revolution of the codewheel. The analog encoder reader outputs a quadrature signal comprised of sine and cosine signals. The quadrature signal is converted to a magnitude signal that is sampled in order to generate a rate of change (ROC) signal, which increases the signal-to-noise ratio. An algorithm using the characteristic shape of the ROC home pulse signal can then be applied to the ROC signal to increases robustness of detecting the home pulse.