Patents by Inventor Amit Chhetri

Amit Chhetri has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11205438
    Abstract: A device capable of motion includes an acoustic echo canceller for cancelling a reference signal from received audio data. The device updates an adaptive filter as the device moves to reflect the changing audio channel between a loudspeaker and a microphone of the device. A step size for changing coefficients of the filter is determined based on its velocity. A number of iterations for updating the filter using a frame of audio data is also determined based on the velocity.
    Type: Grant
    Filed: August 13, 2019
    Date of Patent: December 21, 2021
    Assignee: Amazon Technologies, Inc.
    Inventor: Amit Chhetri
  • Patent number: 11159878
    Abstract: A device capable of moving a component of the device motion is capable of determining audio data corresponding to a direction relative to the device (“beamforming”). When the component moves, the device determines a new position of the component and selects one of a set of beamforming filter coefficients corresponding to the position. Using the filter coefficients, the device determines the directional audio data.
    Type: Grant
    Filed: August 15, 2019
    Date of Patent: October 26, 2021
    Assignee: Amazon Technologies, Inc.
    Inventors: Navin Chatlani, Amit Chhetri, Ananth Raghavendra, Srivatsan Kandadai
  • Patent number: 9319783
    Abstract: Residual echo that remains after an echo cancellation process may interfere with speech recognition. If near-end speech is detected in an audio input signal, a controller may attenuate the audio playback signal. Too much attenuation may disturb playback, whereas too little attenuation may not improve speech recognition. Accordingly, features are disclosed for attenuating an audio playback signal based at least in part on residual echo level.
    Type: Grant
    Filed: February 19, 2014
    Date of Patent: April 19, 2016
    Assignee: Amazon Technologies, Inc.
    Inventors: William Folwell Barton, Amit Chhetri
  • Patent number: 8416946
    Abstract: A regression-based residual echo suppression (RES) system and process for suppressing the portion of the microphone signal corresponding to a playback of a speaker audio signal that was not suppressed by an acoustic echo canceller (AEC). In general, a prescribed regression technique is used between a prescribed spectral attribute of multiple past and present, fixed-length, periods (e.g., frames) of the speaker signal and the same spectral attribute of a current period (e.g., frame) of the echo residual in the output of the AEC. This automatically takes into consideration the correlation between the time periods of the speaker signal. The parameters of the regression can be easily tracked using adaptive methods. Multiple applications of RES can be used to produce better results and this system and process can be applied to stereo-RES as well.
    Type: Grant
    Filed: September 24, 2010
    Date of Patent: April 9, 2013
    Assignee: Microsoft Corporation
    Inventors: Amit Chhetri, Arungunram Surendran, Jack Stokes, John Platt
  • Patent number: 8275120
    Abstract: An acoustic echo cancellation technique. The present adaptive acoustic echo cancellation technique employs a plurality of acoustic echo cancellation filters which use different adaptation techniques which may employ different parameters such as step size, to improve both the adaptation algorithm convergence time and misadjustment over previously known acoustic echo cancellation techniques.
    Type: Grant
    Filed: May 30, 2006
    Date of Patent: September 25, 2012
    Assignee: Microsoft Corp.
    Inventors: Jack W. Stokes, III, Dinei Florencio, Amit Chhetri
  • Publication number: 20110013781
    Abstract: A regression-based residual echo suppression (RES) system and process for suppressing the portion of the microphone signal corresponding to a playback of a speaker audio signal that was not suppressed by an acoustic echo canceller (AEC). In general, a prescribed regression technique is used between a prescribed spectral attribute of multiple past and present, fixed-length, periods (e.g., frames) of the speaker signal and the same spectral attribute of a current period (e.g., frame) of the echo residual in the output of the AEC. This automatically takes into consideration the correlation between the time periods of the speaker signal. The parameters of the regression can be easily tracked using adaptive methods. Multiple applications of RES can be used to produce better results and this system and process can be applied to stereo-RES as well.
    Type: Application
    Filed: September 24, 2010
    Publication date: January 20, 2011
    Applicant: Microsoft Corporation
    Inventors: Amit Chhetri, Arungunram C. Surendran, Jack W. Stokes, III, John C. Platt
  • Patent number: 7813499
    Abstract: A regression-based residual echo suppression (RES) system and process for suppressing the portion of the microphone signal corresponding to a playback of a speaker audio signal that was not suppressed by an acoustic echo canceller (AEC). In general, a prescribed regression technique is used between a prescribed spectral attribute of multiple past and present, fixed-length, periods (e.g., frames) of the speaker signal and the same spectral attribute of a current period (e.g., frame) of the echo residual in the output of the AEC. This automatically takes into consideration the correlation between the time periods of the speaker signal. The parameters of the regression can be easily tracked using adaptive methods. Multiple applications of RES can be used to produce better results and this system and process can be applied to stereo-RES as well.
    Type: Grant
    Filed: March 31, 2005
    Date of Patent: October 12, 2010
    Assignee: Microsoft Corporation
    Inventors: Amit Chhetri, Arungunram Surendran, Jack Stokes, John Platt
  • Publication number: 20060222172
    Abstract: A regression-based residual echo suppression (RES) system and process for suppressing the portion of the microphone signal corresponding to a playback of a speaker audio signal that was not suppressed by an acoustic echo canceller (AEC). In general, a prescribed regression technique is used between a prescribed spectral attribute of multiple past and present, fixed-length, periods (e.g., frames) of the speaker signal and the same spectral attribute of a current period (e.g., frame) of the echo residual in the output of the AEC. This automatically takes into consideration the correlation between the time periods of the speaker signal. The parameters of the regression can be easily tracked using adaptive methods. Multiple applications of RES can be used to produce better results and this system and process can be applied to stereo-RES as well.
    Type: Application
    Filed: March 31, 2005
    Publication date: October 5, 2006
    Applicant: Microsoft Corporation
    Inventors: Amit Chhetri, Arungunram Surendran, Jack Stokes, John Platt