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:
Jun. 15, 2004
Filed:
Feb. 11, 1998
Lawrence M. Burns, Mountain View, CA (US);
Ravi Ramachandran, San Jose, CA (US);
David Fisher, Menlo Park, CA (US);
Chong Woo, Fremont, CA (US);
Scott Mitchell, San Jose, CA (US);
3Com Corporation, Santa Clara, CA (US);
Abstract
In a system that demodulates a frequency modulated signal using a quadrature detector circuit, an apparatus that tunes the output signal to compensate for any offset in the signal includes an offset adjustment circuit and a control circuit. The offset adjustment circuit is operably coupled to the control circuit which may consist of a DAC and a digital logic such as a computer CPU. The control circuit determines a correction signal in response to a sequence of sampled of the system output, and supplies the correction signal to the offset adjustment circuit. The offset adjustment circuit provides an offset correction signal in response to the correction signal, and combines the offset correction signal with the output of the quadrature detector to provide an offset adjusted signal at an output node.