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:
Jul. 16, 2002
Filed:
Aug. 05, 1997
Richard A. Freeman, Cedar Rapids, IA (US);
Rockwell Collins, Inc., Cedar Rapids, IA (US);
Abstract
A phase locked filter can utilize a divider to provide a source signal. The phase locked filter utilizes a phase comparator circuit to tune a voltage-tuned band pass filter. The voltage-tuned band pass filter as a phase response, wherein the phase difference between the input and the output of the band pass filter is zero when the source signal is provided at the center frequency. The phase comparator circuit adjusts the center frequency of the band pass filter to phase lock the source signal from the divider. In this way, the divider can be utilized to provide a clean source signal without a large amount of noise. The phase comparator circuit preferably includes a phase detector or a phase comparator and an integrator. The voltage-tuned band pass filter preferably includes a varactor.