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:
Dec. 08, 1987
Filed:
Aug. 29, 1986
Applicant:
Inventors:
Harold B Pearce, Austin, TX (US);
Lynn P West, Austin, TX (US);
Assignee:
International Business Machines Corporation, Armonk, NY (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
H04B / ;
U.S. Cl.
CPC ...
375 14 ; 329 50 ; 375 97 ; 455265 ;
Abstract
A method and apparatus are described for phase and frequency locking a reference oscillator to an incoming modulated signal. The method and apparatus enable the carrier recovery of the incoming modulated signal. Phase and frequency locking devices are connected in feedback loops with a coherent detector that determine the amount of phase and frequency error between the reference oscillator of the coherent detector and the incoming modulated signal. The feedback loops correct such frequency and phase error so as to enable the reference oscillator to be in phase and frequency step with the modulated signal.