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:
Aug. 03, 2004
Filed:
May. 16, 2002
Tian-Min Liu, Laguna Niguel, CA (US);
Loke Kun Tan, Laguna Niguel, CA (US);
Steven T. Jaffe, Irvine, CA (US);
Broadcom Corporation, Irvine, CA (US);
Abstract
Improved carrier recovery and symbol timing systems and methods suitable for use in connection with a dual-mode QAM/VSB receiver system is disclosed. Carrier and symbol timing acquisition and tracking loops are phase/frequency locked to an inserted pilot signal provided in an input VSB spectrum at a given frequency. An input spectrum is centered about baseband and the pilot is extracted by an equivalent filter which functions as a bandpass filter having pass bands centered about the pilot frequency. Since the pilot signal's frequency is given, its position in the frequency domain for any sampling frequency, is deterministic. The receiver's sampling frequency is provided such that the relationship is expressed as f =f /4. When tracked by a phase-lock loop, the pilot signal will appear at the correct location in the spectrum if the sampling frequency f is correct, and will be shifted in one direction or the other if the sampling frequency f is too high or too low.