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:
May. 15, 2007
Filed:
Sep. 17, 2002
Joseph Graham Mobley, Dunwoody, GA (US);
Jiening AO, Suwanee, GA (US);
Steven E. Blashewski, Duluth, GA (US);
Florin Farcas, Lawrenceville, GA (US);
John A. Ritchie, Jr., Duluth, GA (US);
Lamar E. West, Jr., Maysville, GA (US);
Joseph Graham Mobley, Dunwoody, GA (US);
Jiening Ao, Suwanee, GA (US);
Steven E. Blashewski, Duluth, GA (US);
Florin Farcas, Lawrenceville, GA (US);
John A. Ritchie, Jr., Duluth, GA (US);
Lamar E. West, Jr., Maysville, GA (US);
Scientific-Atlanta, Inc., Lawrenceville, GA (US);
Abstract
An architecture for providing high-speed access over frequency-division multiplexed (FDM) channels allows transmission of ethernet frames and/or other data across a cable transmission network or other form of FDM transport. The architecture involves downstream and upstream FDM multiplexing techniques to allow contemporaneous, parallel communications across a plurality of frequency channels. Moreover, an automatic frequency control resolves some issues of a free-running clock in an upstream tuner of the central concentrator by performing adjustments based on the average frequency error of a number of active upstream tones. In the preferred embodiments of the present invention, the automatic frequency control (AFC) utilizes a feedback loop for at least each active upstream tone. Also, the average of the active upstream tones is determined and is utilized in providing feedback to adjust the automatic frequency control (AFC).