公开(公告)号：US12112737B1

公开(公告)日：2024-10-08

申请号：US17954815

申请日：2022-09-28

Applicant: Amazon Technologies, Inc.

Inventor： Wan-Chieh Pai ,  Harsha Inna Kedage Rao ,  Andrew Jackson Stockton X

IPC: G10K11/178 ,  H04R3/02

CPC classification number: G10K11/17854 ,  H04R3/02

Abstract: A system configured to perform acoustic feedback control to enable a device to perform hearing enhancement while suppressing acoustic feedback. During hearing enhancement, the device may amplify environmental noise based on a unique hearing profile associated with the user, personalizing equalization settings, a dynamic range, and/or other characteristics to optimize playback audio for the user. The acoustic feedback control may include an acoustic feedback cancellation (AFC) component that uses an adaptive filter to estimate and cancel a feedback signal. In addition, the AFC component may perform entrainment prevention by detecting periodic signals and adjusting an adaptation rate of the adaptive filter accordingly. Separately, the device may selectively suppress acoustic feedback by detecting frequency bands representing acoustic feedback (e.g., squeal detection) and applying one or more notch filter(s) to suppress the selected frequency bands (e.g., squeal suppression).

公开(公告)号：US11564036B1

公开(公告)日：2023-01-24

申请号：US17076584

申请日：2020-10-21

Applicant: Amazon Technologies, Inc.

Inventor： Krishna Kamath Koteshwara ,  Zhen Sun ,  Spencer Russell ,  Tarun Pruthi ,  Yuzhou Liu ,  Wan-Chieh Pai

IPC: H04R3/04 ,  H04R5/04 ,  G10L21/0232 ,  G01S15/04 ,  H04R5/027 ,  G10L21/0208

Abstract: Techniques for presence-detection devices to detect movement of a person in an environment by emitting ultrasonic signals using a loudspeaker that is concurrently outputting audible sound. To detect movement by the person, the devices characterize the change in the frequency, or the Doppler shift, of the reflections of the ultrasonic signals off the person caused by the movement of the person. However, when a loudspeaker plays audible sound while emitting the ultrasonic signal, audio signals generated by microphones of the devices include distortions caused by the loudspeaker. These distortions can be interpreted by the presence-detection devices as indicating movement of a person when there is no movement, or as indicating lack of movement when a user is moving. The techniques include processing audio signals to remove distortions to more accurately identify changes in the frequency of the reflections of the ultrasonic signals caused by the movement of the person.