US 11,700,486 B2
Audible howling control systems and methods
Amos Schreibman, Hod Hasharon (IL)
Assigned to GM GLOBAL TECHNOLOGY OPERATIONS LLC, Detroit, MI (US)
Filed by GM GLOBAL TECHNOLOGY OPERATIONS LLC, Detroit, MI (US)
Filed on Aug. 4, 2021, as Appl. No. 17/394,237.
Prior Publication US 2023/0044336 A1, Feb. 9, 2023
Int. Cl. H04R 3/02 (2006.01); G10L 21/0232 (2013.01); G10L 21/0216 (2013.01); G10L 21/0208 (2013.01)
CPC H04R 3/02 (2013.01) [G10L 21/0232 (2013.01); G10L 2021/02082 (2013.01); G10L 2021/02163 (2013.01)] 18 Claims
OG exemplary drawing
 
1. An audio system comprising:
a speaker;
a microphone that generates a microphone signal based on sound output from the speaker;
a mixer module configured to generate a mixed signal by mixing the microphone signal with an audio signal;
a filter module configured to filter the mixed signal to produce a filtered signal and to apply the filtered signal to the speaker; and
a detector module configured to determine a howling frequency in the microphone signal attributable to sound output from the speaker,
wherein the filter module is configured to decrease a magnitude of the mixed signal at the howling frequency, and
wherein the detector module is configured to determine the howling frequency based on a comparison of the filtered signal applied to the speaker at a first time and the microphone signal at a second time that is after the first time.