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. 16, 1997
Filed:
Apr. 21, 1995
Applicant:
Inventors:
Assignee:
Scientific-Atlanta, Inc., Norcross, GA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04L / ;
U.S. Cl.
CPC ...
375344 ; 375326 ; 375329 ; 4551641 ;
Abstract
In a receiver for receiving a carrier modulated with data, there is provided a system for locating and tracking said carrier. The carrier is located by sweeping a frequency range containing said carrier. False lockup are inherent when a wide frequency sweep demodulator attempts to lock onto a carrier, and the system recognizes such lockups by monitoring data from a Viterbi error correction circuit. On false lockup, the system breaks the lockup and continues the sweep until the true data carrier is located and tracked.