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. 15, 2009
Filed:
May. 12, 2006
Weizhong Chen, Austin, TX (US);
Weizhong Chen, Austin, TX (US);
Freescale Semiconductor, Inc., Austin, TX (US);
Abstract
A FCCH Burst detector includes a tone detection filter centered at 67.7 KHz, a tone rejection filter centered at −67.7 KHz, moving average power calculation for the two filter outputs, and a detection logic. A FCCH burst is detected when the ratio of the moving average power of the tone detection filter output to that of the tone rejection filter output is larger than a threshold for a period longer than a threshold. The FB tone end time is detected when the ratio falls back to a threshold or the moving average power of the tone detection filter output falls below a threshold of the average power of the tone detection filter output over a predetermined period. The tone detection filter and the tone rejection filter is implemented by first frequency-shifting the received signal by −67.7 KHz and +67.7 KHz in parallel, then passing the two frequency-shifted signals through two separate low-pass filters.