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. 22, 1992
Filed:
May. 28, 1991
Applicant:
Inventors:
George H Rokos, Bishop's Stortford, GB;
Peter E Morley, Rayne, GB;
Assignee:
Northern Telecom Limited, Montreal, CA;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01K / ;
U.S. Cl.
CPC ...
374117 ; 374163 ; 310311 ; 310371 ; 331 66 ; 331163 ; 73579 ;
Abstract
The temperature of a quartz crystal oscillator is determined by comparison of a pair of inharmonically related overtone oxcillations of the same vibrational type, e.g. a thickness shear mode, and of the same overtone order. The use of inharmonically related signals relaxes the contraints on crystal design. The technique may be employed in a crystal controlled frequency synthesizer to provide a feedback signal for maintaining constant output frequency.