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. 03, 2003
Filed:
Jan. 26, 2001
Raymond Louis Barrett, Jr., Ft. Lauderdale, FL (US);
Barry Herold, Barrington, IL (US);
Scott Humphreys, Greensboro, NC (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A circuit ( ) for generating a ratio signal indicating a ratio of frequency error to signal magnitude of an input signal includes an FM ratio detector ( ) and a sigma-delta analog-to-digital converter ( ). The FM ratio detector ( ) is responsive to the input signal and generates a magnitude signal and an error signal. The magnitude signal is representative of a magnitude of the input signal and the error signal is representative of a frequency error of the input signal relative to a preselected frequency. The sigma-delta analog-to-digital converter ( ), which is responsive to the filtered magnitude signal and the filtered error signal, generates a stream of logic “1's” and logic “0's” that are indicative of a ratio of the filtered error signal to the filtered magnitude signal. Thus, the sigma-delta analog-to-digital converter generates the ratio signal ( ).