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:
Feb. 10, 1998
Filed:
Dec. 09, 1994
Peter Chu, Poway, CA (US);
Other;
Abstract
The GPS-disciplined clock consists of two digital phase locked loops. The first, Loop 1, tracks the crystal oscillator's third overtone vs. fundamental frequency variation with a numerical controlled oscillator, NCO1; The second digital phase locked loop, Loop 2, tracks the GPS satellite receiver's 1PPS signal vs. the crystal oscillator's frequency counter output variation with another numerical controlled oscillator, NCO2. When the satellites are in view, the embedded computer writes the two NCOs tracking record onto a memory; while the satellites are not in view, the computer directs a digital frequency synthesizer to generate frequency according to the tracking records stored in the memory. The hardware implementation of the inventive design is mostly digital, but a very-large-scale ASIC can be used to miniaturize the whole GPS-Synchronized clock system, making it a battery-powered, truly portable, and easy to be integrated into other instruments.