Adaptive Filtering Patents (Class 379/406.08)
  • Patent number: 11323804
    Abstract: An apparatus of reducing feedback noise in an acoustic system, the apparatus comprising: a first input for receiving a first signal derived from a first microphone associated with a first channel, the first signal comprising a first set of frequency sub-bands; a second input for receiving a second signal derived from a second microphone associated with a second channel, the second signal comprising second set of frequency sub-bands, the first and second sets of frequency sub-bands having matching frequency ranges, each frequency sub-band of the first and second sets of frequency sub-bands having a frequency of greater than a threshold frequency; and one or more processors configured to: determining feedback at a first speaker associated with the first channel; and responsive to determining feedback, mix each of the first set of frequency sub-bands with a corresponding one of the second set of frequency sub-bands to generate a mixed output signal comprising a mixed set of frequency sub-bands; wherein the mixin
    Type: Grant
    Filed: January 28, 2020
    Date of Patent: May 3, 2022
    Assignee: Cirrus Logic, Inc.
    Inventors: Henry Chen, Tom Harvey, Brenton Steele
  • Patent number: 11303313
    Abstract: The present invention provides an interference cancellation circuit, wherein the interference cancellation circuit includes a PAPR detection circuit, a control circuit and a filter. In the operations of the interference cancellation circuit, the PAPR detection circuit is configured to detect a PAPR of a signal in a spectrum in a real-time manner to generate a detection result. The control circuit is configured to generate a control signal according to the detection result. The filter is configured to determine a filtering frequency point of the filter according to the control signal, and to filter the signal to generate an output signal.
    Type: Grant
    Filed: January 12, 2021
    Date of Patent: April 12, 2022
    Assignee: Realtek Semiconductor Corp.
    Inventor: Chih-Nung Hsieh
  • Patent number: 11303758
    Abstract: Systems and methods for improved acoustic echo cancellation are provided. In various embodiments, a microphone located in the loudspeaker enclosure provides a first signal that is used to estimate the loudspeaker displacement which is proportional to the sound pressure level (SPL) inside the enclosure. A second signal is then derived by mapping the displacement to the loudspeaker's force factor (Bl(x)) and then modulating this by a measured current to a voice coil inside the speaker to provide an estimate of the force acting on the moving mass of the loudspeaker. The first signal is highly correlated with the echo signal for low frequencies and the second signal is highly correlated with the echo signal for high frequencies. The two signals are then combined to provide a single improved AEC reference signal.
    Type: Grant
    Filed: May 28, 2020
    Date of Patent: April 12, 2022
    Assignee: Knowles Electronics, LLC
    Inventor: Andrew D. Unruh
  • Patent number: 11290802
    Abstract: Techniques for detecting a voice command from a user of a hearable device. The hearable device may include an in-ear facing microphone to capture sound emitted from an ear of the user, and an exterior facing microphone to capture sound emitted from an exterior environment of the user. The in-ear microphone may generate an in-ear audio signal representing the sound emitted from the ear, and the exterior microphone may generate an exterior audio signal representing sound from the exterior environment. The hearable device may include components to determine correlations or similarities between the in-ear audio signal and exterior audio signal, which indicate that the audio signals represent sound emitted from the user. Further, the components may perform voice activity detection to determine that the sound emitted from the user is a voice command, and proceed to perform further voice-processing techniques.
    Type: Grant
    Filed: January 30, 2018
    Date of Patent: March 29, 2022
    Assignee: Amazon Technologies, Inc.
    Inventors: Dibyendu Nandy, Milos Jorgovanovic, Carlo Murgia
  • Patent number: 11276417
    Abstract: A software-based conferencing platform is provided. The platform comprises a plurality of audio sources providing input audio signals, the audio sources including a virtual audio device driver configured to receive far-end input audio signals from a conferencing software module, and a network audio library configured to receive near-end input audio signals from one or more near-end audio devices. The platform further comprises a digital signal processing component configured to receive the input audio signals from the audio sources and generate audio output signals based the received signals, the digital signal processing component comprising an acoustic echo cancellation module configured to apply acoustic echo cancellation techniques to one or more of the near-end input audio signals.
    Type: Grant
    Filed: May 28, 2019
    Date of Patent: March 15, 2022
    Assignee: SHURE ACQUISITION HOLDINGS, INC.
    Inventors: Leif Josef Moravy, Mathew T. Abraham, Paul Gunia, John Casey Gibbs, Lucas Brant Farran
  • Patent number: 11277518
    Abstract: The disclosed teleconferencing methods involve detecting a howl state during a teleconference which involves two or more teleconference client locations and a teleconference server. The teleconference server is configured for providing full-duplex audio connectivity between the teleconference client locations. The howl state is a state of acoustic feedback involving two or more teleconference devices in a teleconference client location. Detecting the howl state involves an analysis of both spectral and temporal characteristics of teleconference audio data. The disclosed teleconferencing methods involve determining which client location is causing the howl state and involve mitigating the howl state or sending a howl state detection message.
    Type: Grant
    Filed: September 27, 2018
    Date of Patent: March 15, 2022
    Assignee: Dolby Laboratories Licensing Corporation
    Inventors: Kai Li, David Gunawan, Feng Deng, Qianqian Fang
  • Patent number: 11264045
    Abstract: In an audio processing system (300), a filtering section (350, 400): receives subband signals (410, 420, 430) corresponding to audio content of a reference signal (301) in respective frequency subbands; receives subband signals (411, 421, 431) corresponding to audio content of a response signal (304) in the respective subbands; and forms filtered inband references (412, 422, 432) by applying respective filters (413, 423, 433) to the subband signals of the reference signal.
    Type: Grant
    Filed: September 9, 2019
    Date of Patent: March 1, 2022
    Assignee: Dolby Laboratories Licensing Corporation
    Inventors: Dong Shi, Glenn N. Dickins, David Gunawan, Xuejing Sun
  • Patent number: 11252088
    Abstract: A method for managing network congestion is provided. The method comprises: receiving, at a receiver, a packet comprising a timestamp provided by a first clock of a sender; deriving, by the receiver, a latency value based at least in part on the timestamp provided by the first clock and a receipt time provided by a second clock of the receiver; determining a latency change by comparing the latency value with a previous latency value; and determining a state of network congestion based at least in part on the latency change.
    Type: Grant
    Filed: August 30, 2018
    Date of Patent: February 15, 2022
    Assignee: PENSANDO SYSTEMS INC.
    Inventors: Raja Rao Tadimeti, Vijay K. Chander, Diego Crupnicoff, Vishal Jain, Madhava Rao Cheethirala
  • Patent number: 11232809
    Abstract: A method, for preventing the intelligible voice recording is provided. The voice of a subject or interlocutor is recorded for a given time interval thereby providing a voice recording. The voice recording is cut into shorter time interval segments thereby providing a set of voice recording segments. The set of voice recording segments is mixed in a randomly rearranged order. The mixed set of voice recording segments is spliced into a single randomly mixed voice recording. Emitting the randomly mixed voice recording during speaking of the subject or interlocutor prevents the intelligible recording of the voice of the subject or interlocutor.
    Type: Grant
    Filed: August 27, 2020
    Date of Patent: January 25, 2022
    Assignee: 12539322 CANADA INC.
    Inventor: Alexandre Santos
  • Patent number: 11128498
    Abstract: A digital circuit for implementing a channel-tracking functionality, in which an adaptive (e.g., FIR) filter is updated based on reinforcement learning. In an example embodiment, the adaptive filter may be updated using an LMS-type algorithm. The digital circuit may also include an electronic controller configured to change the convergence coefficient of the LMS algorithm using a selection policy learned by applying a reinforcement-learning technique and based on residual errors and channel estimates received over a sequence of iterations. In some embodiments, the electronic controller may include an artificial neural network. An example embodiment of the digital circuit is advantageously capable of providing improved performance after the learning phase, e.g., for communication channels exhibiting variable dynamicity patterns, such as those associated with aerial copper cables or some wireless channels.
    Type: Grant
    Filed: February 25, 2020
    Date of Patent: September 21, 2021
    Assignee: Nokia Solutions and Networks OY
    Inventor: Paschalis Tsiaflakis
  • Patent number: 11107488
    Abstract: A system configured to perform echo cancellation using a reduced number of reference signals. The system may perform multi-channel acoustic echo cancellation (MCAEC) processing on a first portion of a microphone audio signal that corresponds to early reflections and may perform single-channel acoustic echo cancellation (AEC) processing on a second portion of the microphone audio signal that corresponds to late reverberations. For example, the system may use MCAEC processing on a plurality of reference audio signals to generate a first echo estimate signal and may subtract the first echo estimate signal from the microphone audio signal to generate a residual audio signal. The system may delay the first echo estimate signal, perform the AEC processing to generate a second echo estimate signal, and subtract the second echo estimate signal from the residual audio signal to generate an output audio signal. This reduces an overall complexity associated with performing echo cancellation.
    Type: Grant
    Filed: October 24, 2019
    Date of Patent: August 31, 2021
    Assignee: AMAZON TECHNOLOGIES, INC.
    Inventors: Mohamed Mansour, Shobha Devi Kuruba Buchannagari
  • Patent number: 11095486
    Abstract: A digital circuit for implementing a channel-tracking functionality, in which an adaptive (e.g., FIR) filter is updated based on reinforcement learning. In an example embodiment, the adaptive filter may be updated using an LMS-type algorithm. The digital circuit may also include an electronic controller configured to change the convergence coefficient of the LMS algorithm using a selection policy learned by applying a reinforcement-learning technique and based on residual errors and channel estimates received over a sequence of iterations. In some embodiments, the electronic controller may include an artificial neural network. An example embodiment of the digital circuit is advantageously capable of providing improved performance after the learning phase, e.g., for communication channels exhibiting variable dynamicity patterns, such as those associated with aerial copper cables or some wireless channels.
    Type: Grant
    Filed: February 25, 2020
    Date of Patent: August 17, 2021
    Assignee: Nokia Solutions and Networks OY
    Inventor: Paschalis Tsiaflakis
  • Patent number: 11095769
    Abstract: Techniques to dynamically engage echo cancellation are described. In one embodiment, an apparatus may comprise a streaming component operative to establish a audio connection between the first client device and a second client device via the network interface controller; and receive a far-end audio stream at the first client device from the second client device via the audio connection; an audio capture component operative to capture a near-end audio stream at the first client device; and an echo processing component operative to compare the near-end audio stream and the far-end audio stream to determine whether a far-end echo is present in the near-end audio stream; and use an echo-cancellation module at the first client device where the far-end echo is present in the near-end audio stream. Other embodiments are described and claimed.
    Type: Grant
    Filed: January 23, 2019
    Date of Patent: August 17, 2021
    Assignee: WHATSAPP LLC.
    Inventors: Manpreet Singh, YuanYuan Wang
  • Patent number: 11062717
    Abstract: Systems and methods for processing an audio signal are provided for replay on an audio device. An audio signal is spectrally decomposed into a plurality of subband signals using band pass filters. Each of the subband signals are provided to a respective modulator and subsequently, from the modulator output, provided to a respective first processing path that includes a first dynamic range compressor, DRC. Each subband signal is feedforward compressed by the respective first DRC to obtain a feedforward-compressed subband signal, wherein the first DRC is slowed relative to an instantaneous DRC. Subsequently, each feedforward-compressed subband signal is provided to a second processing path that includes a second DRC, wherein the feedforward-compressed subband signal is compressed by the respective second DRC and outputted to the respective modulator. Modulation of the subband signals is then performed in dependence on the output of the second processing path.
    Type: Grant
    Filed: June 13, 2019
    Date of Patent: July 13, 2021
    Assignee: Mimi Hearing Technologies GmbH
    Inventor: Nicholas R. Clark
  • Patent number: 11039015
    Abstract: An apparatus and/or method discloses a video conference with enhanced audio quality using high-fidelity audio sharing (“HAS”). In one embodiment, a network connection between a first user equipment (“UE”) and a second UE is established via a communication network for providing an interactive real-time meeting. After sending a first calibration audio signal from the first UE to the second UE, a second calibration audio signal is retuned from the second UE to the first UE according to the first calibration audio signal. Upon identifying a far end audio (“FEA”) delay based on the first calibration audio signal and the second calibration audio signal, a first mixed audio data containing the first shared audio data and first FEA data is fetched from an audio buffer. The first FEA data is subsequently removed or extracted from the mixed audio data in response to the FEA delay.
    Type: Grant
    Filed: March 19, 2020
    Date of Patent: June 15, 2021
    Assignee: Zoom Video Communications, Inc.
    Inventors: Zhaofeng Jia, Huipin Zhang
  • Patent number: 11017789
    Abstract: Example techniques involve noise-robust acoustic echo cancellation. An example implementation may involve causing one or more speakers of the playback device to play back audio content and while the audio content is playing back, capturing, via the one or more microphones, audio within an acoustic environment that includes the audio playback. The example implementation may involve determining measured and reference signals in the STFT domain. During each nth iteration of an acoustic echo canceller (AEC): the implementation may involve determining a frame of an output signal by generating a frame of a model signal by passing a frame of the reference signal through an instance of an adaptive filter and then redacting the nth frame of the model signal from an nth frame of the measured signal. The implementation may further involve determining an instance of the adaptive filter for a next iteration of the AEC.
    Type: Grant
    Filed: October 14, 2019
    Date of Patent: May 25, 2021
    Assignee: Sonos, Inc.
    Inventor: Daniele Giacobello
  • Patent number: 10984778
    Abstract: An adaptive filter includes a frequency domain adaptation block that analyzes a statistic of coefficient movement in the frequency domain. The adaption block adjusts, in the frequency domain, a parameter (step size or leakage factor) that affects speed of convergence of the adaptive filter based on the analyzed statistic of filter coefficient movement. The filter includes an associated coefficient, statistic of coefficient movement, and parameter for each frequency bin. The coefficients may be complex numbers, and separate real and imaginary statistics and parameters are maintained. The statistic may be direction counts of the filter coefficient movement. The step size may be adjusted to a predetermined minimum value when the current direction of movement of the filter coefficient is different than the predominant direction and otherwise the step size is adjusted approximately proportionally to an amount of predominance by a value based on a direction count of the filter coefficient movement.
    Type: Grant
    Filed: July 19, 2019
    Date of Patent: April 20, 2021
    Assignee: Cirrus Logic, Inc.
    Inventors: Dayong Zhou, Chin Huang Yong
  • Patent number: 10964305
    Abstract: A method of suppressing residual echo includes calculating a spectral mismatch of an acoustic echo canceler based upon a program content signal and a residual signal; determining a set of filter coefficients based at least in part upon a selected spectral mismatch; filtering the residual signal based upon the set of filter coefficients; freezing the calculation of the selected spectral mismatch in response to detecting a double talk condition in the residual signal; waiting a predetermined hold period in response to detecting that the double talk condition has ended; and, after the predetermined hold period, resuming the calculation of the spectral mismatch based upon the program content signal and the residual signal.
    Type: Grant
    Filed: May 20, 2019
    Date of Patent: March 30, 2021
    Assignee: BOSE CORPORATION
    Inventors: Elie Bou Daher, Cristian M. Hera
  • Patent number: 10958345
    Abstract: An echo cancellation method includes steps of (a) extracting phase-distortion estimates, (b) reconstructing an echo signal, (c) generating a clean signal, and (d) producing a primary signal. Step (a) includes extracting, from a first phase signal, a plurality of phase-distortion estimates, the first phase signal having been estimated from an echo-corrupted signal received at a first coherent transceiver of a coherent optical network. Step (b) includes reconstructing an echo signal from the plurality of phase-distortion estimates and a transmitted signal transmitted by the first coherent transceiver. Step (c) includes generating a clean signal as a difference between the reconstructed echo signal and the first phase signal. Step (d) includes producing a primary signal by mapping each of a plurality of clean-phase estimates of the clean signal to one of a plurality of constellation symbols associated with a modulation scheme of the primary signal.
    Type: Grant
    Filed: May 7, 2020
    Date of Patent: March 23, 2021
    Assignee: CABLE TELEVISION LABORATORIES, INC.
    Inventors: Mu Xu, Zhensheng Jia, Junwen Zhang, Haipeng Zhang, Luis Alberto Campos
  • Patent number: 10943597
    Abstract: A method for controlling volume in an apparatus having a speaker and a microphone includes receiving, at the microphone, external noise and speech of a user, and calculating sound pressure of the noise received by the microphone. The method further includes performing exception processing of the sound pressure of some or all of the noise using the calculated sound pressure and one of a speech utterance state, a speech receiving state, or a temporal length state, of the noise, mapping volume of the speech in response to the sound pressure of the external noise, synthesizing speech guidance into a sound file, outputting the sound file, via the speaker, according to the mapped volume.
    Type: Grant
    Filed: February 14, 2019
    Date of Patent: March 9, 2021
    Assignee: LG ELECTRONICS INC.
    Inventors: Minook Kim, Sewan Gu, Jinho Sohn, Tack Sung Choi
  • Patent number: 10938994
    Abstract: Techniques for acoustic echo cancellation are described herein. In an example embodiment, a system comprises a speaker, a microphone array with multiple microphones, a beamformer (BF) logic and an acoustic echo canceller (AEC) logic. The speaker is configured to receive a reference signal. The BF logic is configured to receive audio signals from the multiple microphones and to generate a beamformed signal. The AEC logic is configured to receive the beamformed signal and the reference signal. The AEC logic is also configured to compute a vector of bias coefficients multiple times per time frame, to compute a background filter coefficient based on the vector of bias coefficients, to apply a background filter to the reference signal and the beamformed signal based on the background filter coefficient, to generate a background cancellation signal, and to generate an output signal based at least on the background cancellation signal.
    Type: Grant
    Filed: June 19, 2019
    Date of Patent: March 2, 2021
    Assignee: Cypress Semiconductor Corporation
    Inventors: Ted Wada, Ashutosh Pandey
  • Patent number: 10937418
    Abstract: A system configured to improve echo cancellation for nonlinear systems. The system generate reference audio data by isolating portions of microphone audio data that correspond to playback audio data. For example, the system may determine a correlation between the playback audio data and the microphone audio data in individual time-frequency bands in a frequency domain. In some examples, the system may substitute microphone audio data associated with output audio for the playback audio data. The system may generate the reference audio data based on portions of the microphone audio data that have a strong correlation with the playback audio data. The system may generate the reference audio data by selecting these portions of the microphone audio data or by performing beamforming. This results in precise time alignment between the reference audio data and the microphone audio data, improving performance of the echo cancellation.
    Type: Grant
    Filed: January 4, 2019
    Date of Patent: March 2, 2021
    Assignee: Amazon Technologies, Inc.
    Inventors: Navin Chatlani, Krishna Kamath Koteshwara, Trausti Thor Kristjansson, Inseok Heo, Robert Ayrapetian
  • Patent number: 10937441
    Abstract: A system configured to improve audio processing by adaptively selecting target signals based on current system conditions. For example, a device may select a target signal based on a highest signal quality metric when only the local speech is present (e.g., during near-end single-talk conditions), as this maximizes an amount of energy included in the output audio signal. In contrast, the device may select the target signal based on a lowest signal quality metric when only the remote speech is present (e.g., during far-end single-talk conditions), as this minimizes an amount of energy included in the output audio signal. In addition, the device may track positions of the local speech and the remote speech over time, enabling the device to accurately select the target signal when both local speech and remote speech is present (e.g., during double-talk conditions).
    Type: Grant
    Filed: January 4, 2019
    Date of Patent: March 2, 2021
    Assignee: Amazon Technologies, Inc.
    Inventors: Trausti Thor Kristjansson, Xianxian Zhang, Philip Ryan Hilmes
  • Patent number: 10937409
    Abstract: A method for echo cancellation based on microphone signal correlation is disclosed.
    Type: Grant
    Filed: November 8, 2019
    Date of Patent: March 2, 2021
    Assignee: Knowles Electronics, LLC
    Inventors: Murali Mohan Deshpande, Harinarayanan Erumbi Vallabhan
  • Patent number: 10892615
    Abstract: A circuit for mitigating electric shock including an external impedance detection circuit and a test and holdoff circuit. The external impedance detection circuit detects a presence of an external impedance, such as by detecting a relative change in voltage from a startup condition and a test condition. The test and holdoff circuit inhibits operation of a power converter which delivers power to be consumed by a load. The startup condition is defined by mains power applied to the circuit with negligible power consumed by a load. The test condition is defined by non-zero power delivered to the load. According to another aspect, the external impedance detection circuit measures an input voltage using a high input power which is greater than a shock hazard threshold at a duration less than a threshold time duration and determines the presence of the external impedance based on low pass filters having different time constants.
    Type: Grant
    Filed: April 25, 2017
    Date of Patent: January 12, 2021
    Assignee: ENERGY FOCUS, INC.
    Inventors: Jeremiah A. Heilman, John M. Davenport
  • Patent number: 10863272
    Abstract: A system identification device for performing fast real-time identification for a system from input/output data includes a filter robust to disturbance, by setting the maximum energy gain from the disturbance to a filter error, as an evaluation criterion, smaller than a given upper limit. The filter estimates a state estimation value of a state of the system.
    Type: Grant
    Filed: May 21, 2019
    Date of Patent: December 8, 2020
    Assignees: NATIONAL UNIVERSITY CORPORATION, IWATE UNIVERSITY, RION Co., Ltd.
    Inventors: Kiyoshi Nishiyama, Masahiro Sunohara, Nobuhiko Hiruma, Chiho Haruta, Makoto Tateno
  • Patent number: 10832651
    Abstract: A method for substantially eliminating the effect of mechanical vibration on an audio input to a speakerphone system is provided herein, the method comprising: receiving an input sound acoustic signal at a microphone (mic); converting the received input sound acoustic signal into an input sound electrical signal, and outputting the same as a mic output signal; receiving mechanical vibrations at a mechanical vibration sensor (MVS); converting the received mechanical vibrations into a mechanical vibration error signal, and outputting the same as an MVS output signal; and generating a speakerphone system output signal by subtracting the MVS output signal from the mic output signal.
    Type: Grant
    Filed: September 16, 2019
    Date of Patent: November 10, 2020
    Assignee: Crestron Electronics, Inc.
    Inventors: Alexander Marra, Mark Hrozenchik
  • Patent number: 10827076
    Abstract: An acoustic echo path change detector provides a monitoring process in an acoustic echo canceler that removes echo from a microphone signal using an adaptive echo path model that generates an echo estimate from a playback signal. The acoustic echo canceler removes the echo estimate from the microphone signal to provide an echo-canceled output signal. The path change detector receives the microphone signal, the echo estimate and the output signal and determines a rate of change of one or more statistical values dependent on the microphone signal, the echo estimate and the output signal. If the rate of change exceeds a threshold value, the echo path change detector generates an indication that causes a supervisory process to change adaptation of the adaptive echo path model to increase responsiveness to the change in the acoustic echo path, e.g., by increasing the step size.
    Type: Grant
    Filed: March 11, 2020
    Date of Patent: November 3, 2020
    Assignee: CIRRUS LOGIC, INC.
    Inventors: Ying Li, Venkat Anant, Wilbur Lawrence, Seth Suppappola
  • Patent number: 10746840
    Abstract: The systems, devices, and processes described herein may identify a beam of a voice-controlled device that is directed toward a reflective surface, such as a wall. The beams may be created by a beamformer. An acoustic echo canceller (AEC) may create filter coefficients for a reference sound. The filter coefficients may be analyzed to identify beams that include multiple peaks. The multiple peaks may indicate presence of one or more reflective surfaces. Using the amplitude and the time delay between the peaks, the device may determine that it is close to a reflective surface in a direction of the beam.
    Type: Grant
    Filed: May 22, 2017
    Date of Patent: August 18, 2020
    Assignee: Amazon Technologies, Inc.
    Inventors: William Folwell Barton, Kenneth Edgar Hild, II, Ramya Gopalan, Kavitha Velusamy, Amit Singh Chhetri
  • Patent number: 10725148
    Abstract: According to one embodiment, a spatial position measurement apparatus, includes: a transmission unit configured to transmit an ultrasonic wave accompanying with a transmission source identifiable from three or more transmission sensors provided on a first object; a detection unit configured to detect the ultrasonic wave received by two or more reception sensors provided on a second object; a distance calculation unit configured to calculate distances between the transmission sensors and the reception sensors based on propagation time of the ultrasonic wave; and a coordinate calculation unit configured to calculate, in a coordinate system where a position of one group out of a group of the transmission sensors and a group of the reception sensors is fixed, positional coordinates of another group based on the distances.
    Type: Grant
    Filed: August 31, 2017
    Date of Patent: July 28, 2020
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventor: Yohei Inada
  • Patent number: 10657981
    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.
    Type: Grant
    Filed: May 17, 2018
    Date of Patent: May 19, 2020
    Assignee: Amazon Technologies, Inc.
    Inventors: Mohamed Mansour, Robert Ayrapetian
  • Patent number: 10636434
    Abstract: An aspect of this disclosure relates to noise and/or echo suppression for a device in which noise and echo suppression are adaptively determined as noise and echo change in an environment that surrounds the device. An aspect can use a skewed maximal ratio combining technique or a spatial filter with coefficients that are adaptively determined based on a perceptually selected target ratio that is compared to a ratio of sound energies/levels based on a pair of the coefficients. Another aspect relates to the use of information in one frequency band to perform additional noise and/or echo suppression in one or more adjacent frequency bands.
    Type: Grant
    Filed: September 28, 2018
    Date of Patent: April 28, 2020
    Assignee: Apple Inc.
    Inventor: Sean A. Ramprashad
  • Patent number: 10636435
    Abstract: A method for canceling acoustic far-end audio echo content includes high-pass filtering audio content received from a far end and playing the high-pass filtered audio content through a speaker, examining audio content captured by a microphone to detect the presence of audio content in a low-frequency sub band after subtracting high-pass filtered audio content from the audio content captured by the microphone using a least mean square (LMS) adaptive filter. If audio content in a low-frequency sub band is detected in the audio content captured by the microphone, freezing adaptation of the LMS filter and sending to the far end the audio content captured by the microphone after subtracting, and if audio content in a low-frequency sub band is not detected in the audio content captured by the microphone, enabling adaptation of the LMS filter and sending to the far end the audio content captured by the microphone after subtracting.
    Type: Grant
    Filed: January 10, 2019
    Date of Patent: April 28, 2020
    Assignee: Microsemi Semiconductor (U.S.) Inc.
    Inventor: Alden J. Doyle
  • Patent number: 10607627
    Abstract: Techniques related to active acoustic echo cancellation are discussed. Such techniques may include generating an audio output signal having a portion thereof corresponding to a first audio frequency range to negate a response of an audio input device to an output from a speaker in a second audio frequency range at a response negation rate and decimating an audio input signal based on the response negation rate to generate a resultant audio input signal.
    Type: Grant
    Filed: June 24, 2019
    Date of Patent: March 31, 2020
    Assignee: Intel Corporation
    Inventor: Sebastian Rosenkiewicz
  • Patent number: 10602270
    Abstract: Techniques for real-time audio communication including supplying an initial audio signal to an audio signal processor configured to process the initial audio signal and output a processed audio signal to an audio output means, obtaining a loopback audio signal corresponding to the processed audio signal, generating a plurality of audio features for the initial audio signal and the loopback audio signal, generating a similarity measure estimating a similarity of the initial audio signal to the first loopback audio signal based on at least the plurality of audio features, adjusting an adaptation rate for an audio signal processing operation based on at least the similarity measure, and controlling, based on at least the adjusted adaptation rate, an echo cancellation process for cancelling an estimated echo from a near-end audio signal received via an audio input means in proximity to the audio output means.
    Type: Grant
    Filed: November 30, 2018
    Date of Patent: March 24, 2020
    Assignee: Microsoft Technology Licensing, LLC
    Inventors: Karsten Vandborg Sørensen, Puneet Rana
  • Patent number: 10566008
    Abstract: A method of enhancing an audio signal, the method comprising: receiving a plurality of input audio signals from a plurality of microphones; for each of the plurality of input audio signals, generating at an echo cancellation module, at least one output signal, the at least one output signal comprising one or more of an echo cancelled signal, a post-filter signal and a filter tap signal; analysing the plurality of input audio signals and/or the respective at least one output signal to determine a condition at each of the plurality of microphones; selecting one of the at least one output signals based on the determined condition at each of the plurality of microphones; and generating an echo suppressed audio signal by suppressing echo in an audio signal derived from one or more of the plurality of microphones using the selected one of the at least one output signal.
    Type: Grant
    Filed: November 9, 2018
    Date of Patent: February 18, 2020
    Assignee: Cirrus Logic, Inc.
    Inventor: Peter Thorpe
  • Patent number: 10565977
    Abstract: Communication apparatus and devices for surgical robotic systems are described. The communication apparatus can include a user console in communication with a communication device having a surgical tool. The communication device can include a microphone to convert a sound input into an acoustic input signal. The communication device can transmit the acoustic input signal to the user console for reproduction as a sound output for a remote operator. The surgical tool can include an endoscope having several microphones mounted on a housing. The surgical tool can be a sterile barrier having a microphone and a drape. The microphone(s) of the surgical tools can face a surrounding environment such that a tableside staff is a source of the sound input that causes the sound output, and a surgeon and the tableside staff can communicate in a noisy environment. Other embodiments are also described and claimed.
    Type: Grant
    Filed: August 20, 2018
    Date of Patent: February 18, 2020
    Assignee: VERB SURGICAL INC.
    Inventors: Denise Ann Miller, Joan Savall, Geoffrey Robert Russell
  • Patent number: 10504501
    Abstract: Described herein is a method and audio capture system for suppressing noise due to mechanical disturbances in an audio capture system. In one embodiment a method includes the steps of: a) receiving an input audio signal from a microphone; b) receiving an input reference signal separate from the input audio signal; c) processing the input reference signal to generate a control signal for identifying a noise event; d) in response to the control signal, estimating a contribution of the noise event to the input audio signal by applying an adaptive filter to a sliding temporal window of the control signal in the frequency domain; and e) based on the estimated contribution, selectively modifying the input audio signal to generate an output audio signal in which the noise arising from the noise event is at least partially suppressed.
    Type: Grant
    Filed: February 2, 2017
    Date of Patent: December 10, 2019
    Assignee: Dolby Laboratories Licensing Corporation
    Inventors: Glenn N. Dickins, Dong Shi, David Gunawan
  • Patent number: 10506105
    Abstract: The invention relates to an adaptive filter unit, in particular for being used as an echo canceller, comprising a first filter input, configured to receive a first electric audio signal, indicative of a first audio signal A(t), a second filter input, configured to receive a second electric audio signal, indicative of a second audio signal B(t), a processor and a filter output. The processor is configured to calculate and provide audio estimation data X(fn, A(t1, . . .
    Type: Grant
    Filed: March 22, 2019
    Date of Patent: December 10, 2019
    Assignee: SENNHEISER COMMUNICATION A/S
    Inventors: Stig Petri, Svend Feldt
  • Patent number: 10484063
    Abstract: A split radio access network is provided that efficiently transmits beamforming coefficients from a distributed baseband unit device to a remote radio unit device to facilitate beamforming at the remote radio unit. The beamforming coefficients can be determined at the baseband unit device and transmitted along with the data to be beamformed to the remote radio unit device. Due to the large number of antenna ports however, there can still be a very large number of coefficients to transmit, and the disclosure provides for a compressed set of coefficients that reduces the overhead signaling requirements. Instead of sending coefficients for every kth antenna port, the system can select a subset of the coefficients corresponding to a set of k antenna ports which can be used by the remote radio unit to approximate the full set of beamforming coefficients.
    Type: Grant
    Filed: May 4, 2018
    Date of Patent: November 19, 2019
    Assignee: AT&T INTELLECTUAL PROPERTY I, L.P.
    Inventors: Aditya Chopra, Arunabha Ghosh, Milap Majmundar, SaiRamesh Nammi
  • Patent number: 10366704
    Abstract: Techniques related to active acoustic echo cancellation are discussed. Such techniques may include generating an audio output signal having a portion thereof corresponding to a first audio frequency range to negate a response of an audio input device to an output from a speaker in a second audio frequency range at a response negation rate and decimating an audio input signal based on the response negation rate to generate a resultant audio input signal.
    Type: Grant
    Filed: March 16, 2018
    Date of Patent: July 30, 2019
    Assignee: Intel Corporation
    Inventor: Sebastian Rosenkiewicz
  • Patent number: 10354635
    Abstract: Audio pickup systems and methods are provided to enhance an audio signal by removing noise components related to an acoustic environment. The systems and methods receive a primary signal and a reference signal. The reference signal is adaptively filtered and subtracted from the primary signal to minimize an energy content of a resulting output signal.
    Type: Grant
    Filed: November 1, 2017
    Date of Patent: July 16, 2019
    Assignee: Bose Corporation
    Inventors: Jeremy Kemmerer, Alaganandan Ganeshkumar
  • Patent number: 10313509
    Abstract: Updating filter coefficients during echo cancellation is disclosed. In some embodiments, a communication device may include a processor configured to operate a background filter configured as an adaptive filter, operate a foreground filter configured as a fixed filter; and update the foreground filter with coefficients from the background filter responsive to monitoring a history of both a near-end signal energy and an estimated far-end signal energy for a pre-determined time window in which conditions of each of the near-end signal energy and the estimated far-end signal energy are satisfied.
    Type: Grant
    Filed: October 21, 2016
    Date of Patent: June 4, 2019
    Assignee: Sorenson IP Holdings, LLC
    Inventor: Jacob H. Gunther
  • Patent number: 10257598
    Abstract: A direction-switchable transponder of a high speed communications network, e.g., an fiber optic data communications network, is capable of dynamically reversing the data traffic flow of its various communications channels in response to a signal. The signal can specify a number of channels, a channel map, or a required bandwidth. The direction-switchable transponder can receive a signal relating to network bandwidth requirements; select, based on the received signal, one or more fiber optic channels for reversing direction of flow of network traffic; and dynamically and automatically reconfigure the selected fiber optic signal to reverse direction of flow of network traffic. By responding to asymmetric bandwidth requirements, the direction-switchable transponder uses high speed communications network lines more efficiently.
    Type: Grant
    Filed: July 11, 2018
    Date of Patent: April 9, 2019
    Assignee: Facebook, Inc.
    Inventors: Nitin Kumar Goel, Satyajeet Singh Ahuja, Gayathrinath Nagarajan
  • Patent number: 10225395
    Abstract: Techniques to dynamically engage echo cancellation are described. In one embodiment, an apparatus may comprise a streaming component operative to establish a audio connection between the first client device and a second client device via the network interface controller; and receive a far-end audio stream at the first client device from the second client device via the audio connection; an audio capture component operative to capture a near-end audio stream at the first client device; and an echo processing component operative to compare the near-end audio stream and the far-end audio stream to determine whether a far-end echo is present in the near-end audio stream; and use an echo-cancellation module at the first client device where the far-end echo is present in the near-end audio stream. Other embodiments are described and claimed.
    Type: Grant
    Filed: December 9, 2015
    Date of Patent: March 5, 2019
    Assignee: WHATSAPP INC.
    Inventors: Manpreet Singh, YuanYuan Wang
  • Patent number: 10205830
    Abstract: An echo cancellation data synchronization control method is disclosed. The method includes: estimating a sound card delay value; initializing and accumulating a near-end audio buffer queue and a reference audio buffer queue until a difference obtained by subtracting a length of the near-end audio buffer queue from a length of the reference audio buffer queue is greater than or equal to an audio data length corresponding to the sound card delay value; extracting, in accordance with audio frames, audio data from the head of the reference audio buffer queue and the head of the near-end audio buffer queue for echo cancellation processing; obtaining a relative delay value generated by performing echo cancellation processing; and adjusting the sound card delay value according to the relative delay value.
    Type: Grant
    Filed: July 17, 2017
    Date of Patent: February 12, 2019
    Assignee: Tencent Technology (Shenzhen) Company Limited
    Inventors: Xiaoxing Zhou, Yuanjiang Peng
  • Patent number: 10090882
    Abstract: In an echo suppressing apparatus suppressing from a near-end input signal acoustic echo signals caused by a far-end signal, an estimated-echo path characteristic is multiplied by a far-end signal to produce an estimated-echo signal for each frame, and frames of the estimated-echo signals thus obtained are stored in an estimated-echo signal storage. A delay amount estimator calculates the total of differences between the near-end input signal and each estimated-echo signal thus stored, and determines the amount of frame delay having its total of differences minimal. A delay estimated-echo signal calculator uses the amount of frame delay to read out an optimum frame and near frames respectively preceding and following the optimum frame and to calculate a corrected, delay estimated-echo signal. An echo suppressor uses the estimated-echo signal thus corrected to suppress the acoustic echo signals from the near-end input signal.
    Type: Grant
    Filed: December 18, 2014
    Date of Patent: October 2, 2018
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Naoya Kawabata
  • Patent number: 10056092
    Abstract: Methods and apparatus for estimating the power spectral density (PSD) of a residual interference having first and second components after adaptive interference cancellation (AIC). The first component can be estimated using a real-valued FIR filter operating on a time series of PSD estimates of a reference signal, and the second component can be estimated using an exponential decay over time corresponding to a reverberation time using the PSD of the reference signal.
    Type: Grant
    Filed: September 12, 2014
    Date of Patent: August 21, 2018
    Assignee: NUANCE COMMUNICATIONS, INC.
    Inventors: Markus Buck, Tobias Wolff, Naveen Kumar Desiraju
  • Patent number: 9999826
    Abstract: Disclosed herein are a virtual golf simulation device and method for providing stereophonic sound for weather conditions configured such that it is possible for a user to visually and aurally recognize a weather condition, such as wind, when the user plays a round of virtual golf on a virtual golf course using the virtual golf simulation device, and, in particular, the direction or intensity of the wind is expressed via multi-channel stereophonic sound, whereby it is possible to provide a high level of realism even without actually blowing air.
    Type: Grant
    Filed: December 30, 2014
    Date of Patent: June 19, 2018
    Assignee: GOLFZON Co., Ltd.
    Inventors: Young Wook Ro, Han Sup Kim
  • Patent number: 9966931
    Abstract: An RF quasi circulator circuit is described herein. In accordance with one example of the disclosure the circuit includes a receive port, a transmit port and an antenna port as well as a differential amplifier stage having a first input, a second input and an output that is coupled to the receive port. The circuit further includes a first phase shifting element and a second phase shifting element. The first phase shifting element is coupled between the transmit port and the first input of the differential amplifier and the second phase shifting element is coupled between the transmit port and the second input of the differential amplifier. A tunable impedance is coupled to the differential amplifier, and the antenna port is coupled to the first input of the differential amplifier. The tunable impedance is controlled to tune the damping in a signal path from the transmit port to the receive port.
    Type: Grant
    Filed: November 27, 2014
    Date of Patent: May 8, 2018
    Assignee: Infineon Technologies AG
    Inventors: Christoph Wagner, Matthias Porranzl