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:
Jan. 21, 2003
Filed:
Jul. 26, 2001
David Bruce Isaksen, Mountain View, CA (US);
Byron Esten Danzer, Aptos, CA (US);
Wideband Computers, Inc., Mountain View, CA (US);
Abstract
A digital automatic gain control (AGC) system comprising an AGC amplifier configured to scale an input signal by a scale factor, and configured to generate an analog scaled input signal. An analog-to-digital (A/D) converter is configured to sample and convert the analog scaled input signal into a digital scaled input signal. The frequency down converted digital scaled input signal is processed by a power level detector circuit to detect its power level. The logarithmic comparison circuit (LCC) is configured to compare the detected power level of the digital scaled input signal to a predetermined reference signal and configured to generate a digital error signal. Finally, an error processing circuit is configured to process the digital error signal and configured to determine the scale factor of the AGC circuit. The test results show that for any applicable QAM constellation the AGC circuit of the present invention can control the broadest fades (or decreases) in the power level of the input signal with an accuracy up to 200 dB/per second.