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:
Sep. 02, 1997
Filed:
Feb. 21, 1996
Applicant:
Inventors:
David C Chu, Woodside, CA (US);
Jeremy S Sommer, Los Altos, CA (US);
Assignee:
Hewlett-Packard Company, Palo Alto, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01R / ;
U.S. Cl.
CPC ...
327-7 ; 327 10 ; 327 12 ;
Abstract
In the present embodiment, digital phase detection of digital telecommunications signals is based on heterodyning. The frequency of two signals are scaled to different nominal values that are separated by a typically small but finite difference. The two frequencies are then mixed to generate a finite beat frequency. In mixing, phase is preserved and the finite beat frequency phase is in one-to-one correspondence with the signal phase. Phase detection is performed indirectly at the lower finite beat frequency with high resolution and greater ease than direct phase detection.