公开(公告)号：US09773510B1

公开(公告)日：2017-09-26

申请号：US14949567

申请日：2015-11-23

Applicant: Amazon Technologies, Inc.

Inventor： Robert Ayrapetian ,  Yuwen Su ,  Arnaud Jean-Louis Charton

IPC: H03G5/00 ,  H04B3/20 ,  G10L21/055 ,  G10L19/06 ,  G10L21/0232 ,  H04M9/08 ,  H03G3/00 ,  H04B3/23

CPC classification number: G10L21/055 ,  G10L19/06 ,  G10L21/0232 ,  H03G3/00 ,  H04B3/23 ,  H04M9/08 ,  H04M9/082

Abstract: Features are disclosed for measuring and correcting clock drift and propagation delay in an audio system through one or more waveforms embedded in an audio signal. A first device in communication with a speaker may be configured to obtain an audio signal and insert one or more waveforms into the audio signal. For example, the waveforms may be inserted during an interval of time. A second device in communication with a microphone may be configured to detect sound as an audio input signal. The second device may obtain a spectral representation of the audio input signal and determine a rotation based on the spectral representation at the frequency of at least one of the inserted waveforms. Clock drift may be determined based on the rotation.

公开(公告)号：US09747920B2

公开(公告)日：2017-08-29

申请号：US14973274

申请日：2015-12-17

Applicant: Amazon Technologies, Inc.

Inventor： Robert Ayrapetian ,  Philip Ryan Hilmes

IPC: G10L21/0216 ,  H04R5/04 ,  G10L21/0208

CPC classification number: G10L21/0216 ,  G10L21/0208 ,  G10L2021/02082 ,  G10L2021/02166 ,  H04R3/005 ,  H04R5/04 ,  H04R2201/40 ,  H04R2203/12 ,  H04R2420/07

Abstract: An echo cancellation system that performs audio beamforming to separate audio input into multiple directions and determines a target signal and a reference signal from the multiple directions. For example, the system may detect a strong signal associated with a speaker and select the strong signal as a reference signal, selecting another direction as a target signal. The system may determine a speech position and may select the speech position as a target signal and an opposite direction as a reference signal. The system may create pairwise combinations of opposite directions, with an individual direction being selected as a target signal and a reference signal. The system may select a fixed beamformer output for the target signal and an adaptive beamformer output for the reference signal, or vice versa. The system may remove the reference signal (e.g., audio output by the loudspeaker) to isolate speech included in the target signal.

公开(公告)号：US11812237B2

公开(公告)日：2023-11-07

申请号：US17553976

申请日：2021-12-17

Applicant: Amazon Technologies, Inc.

Inventor： Robert Ayrapetian ,  Philip Ryan Hilmes ,  Mohamed Mansour ,  Carlo Murgia

IPC: G10L21/02 ,  H04R3/00 ,  H04R5/04 ,  H04R5/027 ,  G10L21/0224 ,  G06F3/16 ,  G10L21/0272 ,  G10L21/0208 ,  G10L21/0216 ,  G10L25/93 ,  G10L25/51 ,  H03H21/00 ,  G10L25/78

CPC classification number: H04R3/005 ,  G06F3/167 ,  G10L21/02 ,  G10L21/0208 ,  G10L21/0224 ,  G10L21/0272 ,  H04R5/027 ,  H04R5/04 ,  G10L25/51 ,  G10L25/78 ,  G10L25/93 ,  G10L2021/02082 ,  G10L2021/02166 ,  H03H21/0012

Abstract: Techniques for improving adaptive interference cancellation (AIC) using cascaded AIC algorithms are described. To improve an accuracy of detecting speech, a device may perform a first stage of AIC to generate isolated audio data and may generate speech mask data indicating time windows when speech is detected in the isolated audio data. Based on the speech mask data, the device may perform second AIC to generate output audio data, with adaptation of the adaptive filter enabled when the speech is not detected and disabled when the speech is detected. Thus, the first AIC improves the accuracy with which the device detects that speech is present and the second AIC reduces distortion in the output audio data by not updating filter coefficient values when the speech is present. The first AIC may use playback audio data, microphone audio data or beamformed audio data as reference signals.

公开(公告)号：US20220109929A1

公开(公告)日：2022-04-07

申请号：US17553976

申请日：2021-12-17

Applicant: Amazon Technologies, Inc.

Inventor： Robert Ayrapetian ,  Philip Ryan Hilmes ,  Mohamed Mansour ,  Carlo Murgia

IPC: H04R3/00 ,  H04R5/027 ,  G06F3/16 ,  H04R5/04 ,  G10L21/0224 ,  G10L21/0208 ,  G10L21/02 ,  G10L21/0272

Abstract: Techniques for improving adaptive interference cancellation (AIC) using cascaded AIC algorithms are described. To improve an accuracy of detecting speech, a device may perform a first stage of AIC to generate isolated audio data and may generate speech mask data indicating time windows when speech is detected in the isolated audio data. Based on the speech mask data, the device may perform second AIC to generate output audio data, with adaptation of the adaptive filter enabled when the speech is not detected and disabled when the speech is detected. Thus, the first AIC improves the accuracy with which the device detects that speech is present and the second AIC reduces distortion in the output audio data by not updating filter coefficient values when the speech is present. The first AIC may use playback audio data, microphone audio data or beamformed audio data as reference signals.

公开(公告)号：US10657981B1

公开(公告)日：2020-05-19

申请号：US15982392

申请日：2018-05-17

Applicant: Amazon Technologies, Inc.

Inventor： Mohamed Mansour ,  Robert Ayrapetian

IPC: G10L21/0208 ,  H04R1/08 ,  H04M9/08 ,  G06F17/10 ,  G10L15/22 ,  H04R1/28 ,  G10L15/14 ,  G10L15/08

Abstract: Techniques for improving acoustic echo cancellation to attenuate an echo signal generated by a loudspeaker included in a device are described. A system may determine a loudspeaker canceling beam (LCB) (e.g., fixed beam directed to the loudspeaker) and may use the LCB to generate LCB audio data that corresponds to the echo signal. For example, based on a configuration of the loudspeaker relative to microphone(s) of the device, the system may perform simulation(s) to generate a plurality of filter coefficient values corresponding to the loudspeaker. By subtracting the LCB audio data during acoustic echo cancellation, the system may attenuate the echo signal even when there is distortion or nonlinearity or the like caused by the loudspeaker. In some examples, the system may perform acoustic echo cancellation using the LCB audio data and playback audio data.

公开(公告)号：US10109294B1

公开(公告)日：2018-10-23

申请号：US15081155

申请日：2016-03-25

Applicant: Amazon Technologies, Inc.

Inventor： Robert Ayrapetian ,  Philip Ryan Hilmes ,  Yuwen Su

IPC: G10L21/0364 ,  G10L25/84 ,  G10L21/0208 ,  G10L25/78

Abstract: Systems and methods for disabling adaptive echo cancellation functionality for a temporal window are provided herein. In some embodiments, audio data may be received by a voice activated electronic device, where the audio data may include an utterance of a wakeword that may be subsequently followed by additional speech. A start time of when the wakeword began to be uttered may be determined by the voice activated electronic device, and the voice activated electronic device may also send the audio data to a backend system. Adaptive echo cancellation functionality may be disabled at the start time. The backend system may determine an end time of the speech, and may provide an indication to the voice activated electronic device of the end time, which in turn may cause the voice activated electronic device to enable the adaptive echo cancellation functionality at the end time.

公开(公告)号：US09966086B1

公开(公告)日：2018-05-08

申请号：US15184765

申请日：2016-06-16

Applicant: Amazon Technologies, Inc.

Inventor： Kurt Wesley Piersol ,  Preethi Parasseri Narayanan ,  Robert Ayrapetian ,  Arnaud Jean-Louis Charton ,  Gabe Beddingfield ,  Michael Alan Pogue ,  Yuwen Su

IPC: G10L21/0232 ,  G10L21/0264 ,  G10L21/0208 ,  G10L21/0216

CPC classification number: G10L21/0232 ,  G10K11/175 ,  G10L21/0208 ,  G10L21/0264 ,  G10L2021/02082 ,  G10L2021/02166 ,  H04R3/02

Abstract: A system may be configured to interact with a user through speech using a first and second audio devices, where the first device produces audio and the second device captures audio. The second device may be configured to perform acoustic echo cancellation with respect to a microphone signal based on a reference signal provided by the first device. The reference and microphone signals may have the same nominal signal rates. However, the signal rates may drift from each other over time. In order to synchronize the rates of the signals, each of the devices maintains a signal index. The second device compares the values of the two signal indexes over time to determine rate differences between the reference and microphone signals and then corrects for the rate differences.

公开(公告)号：US09966059B1

公开(公告)日：2018-05-08

申请号：US15697088

申请日：2017-09-06

Applicant: Amazon Technologies, Inc.

Inventor： Robert Ayrapetian ,  Philip Ryan Hilmes ,  Carlo Murgia

IPC: G10K11/178 ,  G10L21/0216 ,  H04R1/08 ,  H04R1/32 ,  H04R1/46 ,  H04R3/00

CPC classification number: G10K11/178 ,  G10K11/346 ,  G10L21/0208 ,  G10L21/0216 ,  G10L2021/02165 ,  G10L2021/02166 ,  H04R1/08 ,  H04R1/32 ,  H04R1/46 ,  H04R3/002

Abstract: An acoustic interference cancellation system that performs beamforming using a subset of microphones from a microphone array. For example, a first group of microphones from an array can be used to generate target signals that focus on the direction of the desired speech in the audio and a second group of microphones from the array can be used to generate reference signals that include the environmental noise, audio from a loudspeaker, etc. The reference signals of the second group of microphones can then be used to isolate the actual speech from the target signals of the first group of microphones. The microphone array can be three dimensional, allowing a device to simplify beamforming calculations by selecting subsets of microphones along different planes. In addition, directional microphones and remote microphones may be used to improve a quality of the reference signals.

公开(公告)号：US09820049B1

公开(公告)日：2017-11-14

申请号：US15290383

申请日：2016-10-11

Applicant: Amazon Technologies, Inc.

Inventor： Robert Ayrapetian ,  Arnaud Jean-Louis Charton ,  Yuwen Su

IPC: H04B3/20 ,  H04R3/12 ,  H04R3/02 ,  H04M9/08 ,  H04S7/00

CPC classification number: H04R3/12 ,  H04M9/082 ,  H04R3/02 ,  H04R2227/007 ,  H04R2420/07 ,  H04S7/301 ,  H04S7/305

Abstract: An acoustic echo cancellation (AEC) system that detects and compensates for differences in sample rates between the AEC system and a set of wireless speakers based on a search-based trial-and-error technique. The system individually determines a frequency offset for each microphone-speaker pair using an iterative process, determining an echo-return loss enhancement (ERLE) value for each offset that is tried, and selecting the frequency offset associated with the largest ERLE value.

公开(公告)号：US09787825B1

公开(公告)日：2017-10-10

申请号：US14788032

申请日：2015-06-30

Applicant: Amazon Technologies, Inc.

Inventor： Robert Ayrapetian ,  Arnaud Jean-Louis Charton ,  Yuwen Su ,  Michael Alan Pogue

IPC: H04M9/08 ,  H04M3/00

CPC classification number: H04M3/002 ,  H04B3/20

Abstract: A multi-channel audio communication system is configured to receive highly correlated input audio signals, generated as an example by multiple microphones at a far-end site. Each input audio signal is cyclically stepped through a range of discrete delay amounts, between upper and lower limits, using a step size that is a fraction of the sample period of the input audio signals. Delay cycles applied to the different input audio signals are configured to have different phases, thereby reducing the inter-signal correlation of the input audio signals. The delayed input audio signals are then played by loudspeakers. Microphone output, which may contain sound generated by the loudspeakers, is then subjected to multi-channel acoustic echo cancellation.