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:
Apr. 10, 2007
Filed:
Mar. 13, 2003
Richard A. Kreifeldt, Sandy, UT (US);
Curtis R. Reed, Salt Lake City, UT (US);
Aaron M. Hammond, Eagle Mountain, UT (US);
Richard A. Kreifeldt, Sandy, UT (US);
Curtis R. Reed, Salt Lake City, UT (US);
Aaron M. Hammond, Eagle Mountain, UT (US);
Harman International Industries, Incorporated, Northridge, CA (US);
Abstract
This invention is an audio system capable of identifying frequencies of feedback signals and filters these feedback signals. Frequency interpolation is utilized on a sampled frequency spectrum signal corresponding to a feedback signal, where the frequency interpolation allows the frequency of the feedback signal to be identified, especially where the frequency lies between samples of the frequency spectrum signal. The frequency identification allows a less intrusive filter, such as a notch filter, to be placed at the determined frequency of the feedback to eliminate the feedback signal. The placement of the notch filter reduces the effect on the audio signal provided by the audio system. The audio system may provide adaptive filtering of multiple feedback signals, using a single filter such as a notch filter. The single notch filter is configured to filter the more than one feedback signal, thereby freeing-up notch filters for filtering other feedback signals, or for reducing memory and processing requirements for the processor of the system.