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ECHO CANCELLATION OR SUPPRESSION

Subclass of:

379 - Telephonic communications

Patent class list (only not empty are listed)

Deeper subclasses:

Class / Patent application numberDescriptionNumber of patent applications / Date published
379406060 Using digital signal processing 105
379406050 Residual echo cancellation 7
379406020 Combined diverse function 4
20100183140Method and Apparatus for Double-Talk Detection - The present invention discloses a double-talk detection method and apparatus. The method includes: obtaining a far-end signal frame and a near-end signal frame; and detecting a talk state according to a spectrum difference between the far-end signal frame and the near-end signal frame. The apparatus includes: an obtaining module, adapted to obtain a far-end signal frame and a near-end signal frame; and a spectrum detecting module, adapted to detect a talk state according to a spectrum difference between the far-end signal frame and the near-end signal frame. With the present invention, the talk state is detected according to the spectrum difference between the far-end signal and the near-end signal. Even if nonlinear distortion exists, the precision of detection is not impacted, whereas, the greater the distortion is, the more precise the detection result and the better the detection performance will be.07-22-2010
20080240412Maintaining convergence of a receiver during changing conditions - In one embodiment, the present invention includes an apparatus having an automatic gain control (AGC) stage to receive an input signal from a communication channel physical medium, a first local gain stage coupled to an output of the AGC stage, an equalizer coupled to an output of the first local gain stage, an echo canceler to receive local data to be transmitted along the communication channel physical medium, and a second local gain stage coupled to an output of the echo canceler. Other embodiments are described and claimed.10-02-2008
20120195424MEASURING QUALITY OF EXPERIENCE IN TELECOMMUNICATION SYSTEM - Technologies are generally described for a system for measuring a quality of experience (QoE). In some examples, a quality of experience (QoE) measuring device may include a background noise detecting unit configured to measure a background noise around a near-end talker, and a decision unit configured to determine whether a double talk event detected by a double talk detector is caused by the background noise around the near-end talker.08-02-2012
20090225980GAIN AND SPECTRAL SHAPE ADJUSTMENT IN AUDIO SIGNAL PROCESSING - A signal processing system enhances communication. When an audio signal is detected, an echo component of the detected audio signal may be estimated. A near party communication device may receive an audio signal from a remote party communication device. A characteristic of the received audio signal may be adjusted based on the echo component of the detected audio signal.09-10-2009
379406040 Disable or inhibit function 4
20090196413ANALOG TRUNK AND METHOD FOR OPTIMIZING VOICE QUALITY IN ANALOG TRUNK - A method for optimizing voice quality in an analog trunk is provided. The method includes setting a loop parameter to optimize an Echo Return Loss (ERL) property for a loop distance, generating a tone according to a value of the loop parameter and measuring ERL values from the tone, and setting a loop parameter value corresponding to a smallest ERL value of the measured ERL values, as an optimized loop parameter.08-06-2009
20090116637METHOD FOR SEAMLESS NOISE SUPPRESSION ON WIDEBAND TO NARROWBAND CELL SWITCHING - A method for seamless noise suppression on wideband to narrowband cell switching is described. In one embodiment the method includes applying noise suppression to a telephone signal using a first noise suppressor while operating a telephone in a first operating mode, the first noise suppressor generating an estimate of a noise components of the telephone signal; switching the telephone from the first operating mode to a second operating mode; providing the estimate of the noise component as an input to a second noise suppressor different from the first noise suppressor, when the switching step is performed; and applying noise suppression to the telephone signal using the second noise suppressor by using the estimate of the noise component provided by the first noise suppressor when the switching step is performed.05-07-2009
20110116620DISTRIBUTED SOUND ENHANCEMENT - Sound quality is enhanced in a sound system including handsets and headsets. Handset sound enhancing algorithms are implemented in a handset. The handset automatically determines which, if any, of a plurality of headset sound enhancing algorithms are active in a headset in communication with the handset. The handset determines how to use the handset sound enhancing algorithms in a sound processing channel based on which of the headset sound enhancing algorithms are active in the headset.05-19-2011
20130208884APPARATUS AND METHOD FOR CANCELLING WIDEBAND ACOUSTIC ECHO - Disclosed is an apparatus and method for cancelling a wideband acoustic echo that controls a data flow of data that is transmitted and received using a central processing unit, and calculates data using a calculation processing unit configured to be distinct from the central processing unit.08-15-2013
379406160 Having analog variolosser or attenuator 3
20090202063Controlling Echo During Double-Talk in a Voice Conference - An echo canceller apparatus comprises a receive side attenuator coupled in a receive side signal path that is configured to couple from a conference call bridge to a caller; a convolution processor coupled to the receive side signal path at a convolution processor pick-off point; a double-talk detector coupled to the receive side signal path and to a sending side signal path that is configured to couple from the caller to the conference call bridge; and logic coupled to the receive side attenuator which when executed is responsive to a double-talk condition detected by the double-talk detector and operable to determine a level of echo canceled by the convolution processor, to determine an additional amount of attenuation to introduce, and to activate the receive side attenuator to introduce the additional attenuation.08-13-2009
20120114115Full-Duplex Audio Communication Terminal - A full duplex audio communication terminal (05-10-2012
20110069830Detection and Suppression of Returned Audio at Near-End - Audio from a near-end that has been acoustically coupled at the far-end and returned to the near-end unit is detected and suppressed at the near-end of a conference. First and second energy outputs for separate bands are determined for the near-end audio being sent from the near-end unit and for the far-end audio being received at the near-end unit. The near-end unit compares the first and second energy outputs to one another for each of the bands over a time delay range and detects the return of the sent near-end audio in the received far-end audio based on the comparison. The comparison can use a cross-correlation to find an estimated time delay used for further analysis of the near and far-end energies. The near-end unit suppresses any detected return by muting or reducing what far-end audio is output at its loudspeaker.03-24-2011
Entries
DocumentTitleDate
20130028409APPARATUS AND METHOD FOR ECHO CONTROL IN PARAMETER DOMAIN - The present invention relates to call voice signal processing, and particularly, to apparatus and method for echo control in parameter domain. The apparatus includes: an echo detection module configured to extract parameter domain characteristic parameters of a far-end output signal and a near-end input signal, respectively, through parameter domain decoding, and detect whether a near-end input signal frame is an echo frame according to the parameter domain characteristic parameters; and a transition module configured to re-quantize the fixed codebook gain, the adaptive codebook gain and an LSF prediction error in the near-end input signal frame when the echo detection module detects the near-end input signal frame as a non-echo frame, and replace the original fixed codebook gain, the original adaptive codebook gain and the original LSF in the near-end input signal frame.01-31-2013
20090067615ECHO CANCELLATION USING GAIN CONTROL - A device for reducing echo by controlling microphone and/speaker gain in a telecommunications system is disclosed. An exemplary embodiment of the device may have an echo detector, echo level detector, and a gain controller. The echo detector detects an echo in a transmitted audio communication signal. The echo level detector determines the volume level of the detected echo. The gain control may adjust the gain of a microphone transmitting and/or speaker broadcasting the audio communication signal based on the echo level detected. The gain control and echo cancellation may cooperate with each other.03-12-2009
20110194685METHOD AND SYSTEM FOR NONLINEAR ACOUSTIC ECHO CANCELLATION IN HANDS-FREE TELECOMMUNICATION DEVICES - A method and system for determining and compensating for a non-linearity in a hands-free acoustic telecommunication device is disclosed. The method determines a back electromotive force signal induced in a loudspeaker from at least one of a coil voltage, a current signal and estimates of coil resistance and inductance, estimating at least one of a cone position and a cone velocity from the BEMF integrated with respect to time and determining an estimate of an echo value from a series connection of an estimated inverse of a force factor function primitive and the estimated acoustic impulse response; and outputting the estimated echo value.08-11-2011
20090122975METHOD, SYSTEM AND APPARATUS FOR CONTROLLING AN ECHO CANCELLER DURING FAXING - A method, an apparatus and a system for controlling an echo canceller in faxing are provided. The method includes: after detecting a triggering signal, the signal detecting apparatus enables the echo canceller to be in the initial state if the echo canceller is in the disabled state. In the apparatus and the system provided by embodiments of the present invention, a signal detecting apparatus is configured to detect the signals in the fax system. After a triggering signal is sent in the system, the disabled echo canceller is enabled to be in the initial state. In this way, the disabled echo canceller can be restarted during faxing. In the prior art, the disabled echo canceller is hard to be restarted during faxing. Hence, the technical solution provided by embodiments of the present invention may guarantee the fax reliability and the quality of the faxed images.05-14-2009
20100046738Method and apparatus for DMT crosstalk cancellation - An apparatus for precoding multi-tone modulated transmissions of a plurality of communication channels over bundled subscriber lines. The apparatus includes a pseudo symbol controller and a precoder. The pseudo symbol controller detects a victim communication channel and an interferer communication channel having non-matching symbol rates, and transforms the interferor channel into a pseudo-symbol having both a substantially similar length as a corresponding symbol of the victim channel together with defined tonal characteristics expressed in terms of the interferor channel. The precoder assigns crosstalk coefficients to selected sub-channels or tones of the pseudo symbol and precodes the victim channel with the pseudo symbol using the crosstalk coefficients; thereby generating a precoded victim symbol which exhibits reduced crosstalk between the selected victim and interferor.02-25-2010
20130077776Method, System and Computer Program Product for Acoustic Echo Cancellation - In response to a first signal, a first sound wave is output. A second sound wave is received that includes an acoustic echo of the first sound wave. In response to the second sound wave, a second signal is output that cancels an estimate of the acoustic echo. The estimate of the acoustic echo is iteratively adapted to increase a statistical independence between the first and second signals, irrespective of whether a first voice is present in the first sound wave, and irrespective of whether a second voice is present in the second sound wave.03-28-2013
20090279686ECHO PATH CHANGE DETECTION IN TELECOMMUNICATIONS NETWORKS - In one embodiment, the present invention is a method for detecting an echo path change (EPC) in a telecommunications network. The method detects whether the effectiveness of echo cancellation of an echo canceller has decreased relatively significantly. Once a relatively significant decrease is detected, the method determines whether the decrease was an EPC or an inadvertent detection of double talk (DT). In particular, the method considers whether echo is effectively cancelled over a hangover period. Further, echo return loss (ERL) estimates are generated over the hangover period and compared to a lowest-possible ERL for the network. If both (1) echo cancellation is ineffective and (2) a sufficient number of ERL estimates are not below the worst-case ERL, then an EPC decision is made. If either (1) echo cancellation is effective or (2) a sufficient number of ERL estimates are below the worst-case ERL, then a DT decision is made.11-12-2009
20120183133DEVICE AND METHOD FOR CONTROLLING DAMPING OF RESIDUAL ECHO - The present invention relates to a device, such as a communication device, comprising an adaptive foreground filter configured to calculate a first echo estimation signal based on a first input signal, and an adaptive background filter being more rapidly adapting than the foreground filter and configured to calculate a second echo estimation signal based on said first input signal. Embodiments of the device further comprise damping control means for controlling damping of an echo-cancelled output signal. The device in various embodiments includes that the damping control means is configured to calculate a maximum echo estimation signal using both the first and the second echo estimation signals, and control the damping of the echo-cancelled output signal based on said maximum echo estimation signal and/or a signal derived from said maximum echo estimation signal.07-19-2012
20120219146ADAPTIVE DELAY COMPENSATION FOR ACOUSTIC ECHO CANCELLATION - An acoustic echo cancellation system buffers remote side signals to one or more storage areas. A delay controller filters and delays the remote side signals to correlate the remote side signals to local side signals. An acoustic echo cancellation core pulls the remote side signals from the buffer through a delay controller. A delay estimator generates an estimate of a delay between the buffered remote side signals and the local side signals. The delay estimator renders a confidence level that indicates a degree of likelihood for each potential match between delayed remote side signals and the local side signals. The acoustic echo cancellation core substantially cancels a portion of the echo or reverberation within the local side signals based on the estimate of the delay and the confidence level.08-30-2012
20110075833Echo Canceller With Correlation Using Pre-Whitened Data Values Received By Downlink Codec - Duplex audio communications over a network use compressed audio data, with linear prediction coefficients (LPCs) and variances by which sample values differ from predictions. A adaptive echo canceller for a transceiver develops finite impulse response filter (FIR) coefficients characterizing an echo path between its local audio output and audio input. The received/decompressed audio data is applied to the FIR coefficients, and the predicted echo is subtracted from the uplink signal. Echo is detected as cross-correlation of the receive signal versus the uplink/send signal over time. In one embodiment, the cross-correlation is determined using a pre-whitened receive signal, obtained by adopting the variance values received over the network by the downlink Codec. Apart from the uplink Codec, no speech analysis filter or process is needed. The technique is apt for GSM, AMR and similar compressed audio communications.03-31-2011
20100034372METHOD AND SYSTEM FOR DISTRIBUTED SPEAKERPHONE ECHO CANCELLATION - A speakerphone system includes first and second speakerphones connected via a network and a first processor in the first speakerphone and a second processor in the second speakerphone, each of the speakerphones having a first, active, mode for participating in a call with a telephone and a second, idle, mode, wherein, when the first speakerphone is operating in the first mode and the second speakerphone is operating in the second mode, the first speakerphone is adapted to send voice data packets to the second speakerphone, the second speakerphone is adapted to receive voice data packets from the first speakerphone, perform echo cancellation processing on the voice data packets and send the processed voice data packets back to the first speakerphone, and the first speakerphone is adapted to receive the processed voice data packets from the second speakerphone and use the processed voice data packets in the call.02-11-2010
20090046847ACOUSTIC ECHO CANCELLER USING MULTI-BAND NONLINEAR PROCESSING - An echo canceller (02-19-2009
20110170683Systems and Methods for Echo Cancellation and Echo Suppression - Traditionally, echo cancellation has employed linear adaptive filters to cancel echoes in a two way communication system. The rate of adaptation is often dynamic and varies over time. Disclosed are novel rates of adaptation that perform well in the presence of background noise, during double talk and with echo path changes. Additionally, the echo or residual echo can further be suppressed with non-linear processing performed using joint frequency-time domain processing.07-14-2011
20090074177Echo canceler and echo canceling program - An echo canceler uses an adaptive filter to remove an echo of an incoming far-end signal from an outgoing near-end signal. Filter coefficients are calculated and updated while the far-end signal is active so as to minimize the residual echo. In addition, the far-end signal and near-end signal are sampled to generate simulated far-end and near-end signals, from which substitute filter coefficients are similarly calculated while the far-end signal is silent. When the far-end signal changes from silent to active, the substitute filter coefficients are swapped in as initial values for the filter coefficients, thereby speeding up subsequent convergence of the filter coefficients without significant added computational cost.03-19-2009
20080232577Echo cancellation - A method of determining if an echo canceller comprised in a communication channel that is used to transmit at least one tonal signal and characterized by a model echo path of the channel, is acceptably adapted to cancel echoes in the channel, the method comprising: determining a performance measure how well the canceller cancels echoes of at least one test signal characterized by at least one frequency different from a frequency of the at least one tonal signal; and determining if the canceller is acceptably adapted responsive to the measure.09-25-2008
20090034712Echo cancellation in which sound source signals are spatially distributed to all speaker devices - A system includes microphone devices, echo cancellation mechanism, and speaker devices. Each echo cancellation mechanism corresponds to one of the microphone devices. Each speaker device corresponds to a sound source signal. Each sound source signal is spatially distributed to all the speaker devices, and each echo cancellation mechanism receives as a reference signal a combination of all the sound source signals.02-05-2009
20080292093METHOD AND APPARATUS FOR ECHO CANCELLATION - A technique of echo cancellation in a communication system. A method and/or apparatus of echo cancellation that may be suitable for performing echo cancellation under single talk and double talk conditions. A method and/or apparatus of echo cancellation that may significantly reduce a residual echo in a single talk environment (e.g. present in many telecommunications systems) without distorting a near end signal in a double talk environment. A method and/or apparatus of echo cancellation that may reduce a residual echo in single talk and double talk environments by applying a post-processing technique to an ECLMS algorithm.11-27-2008
20090003586SIGNAL PROCESSOR AND METHOD FOR CANCELING ECHO IN A COMMUNICATION DEVICE - The invention provides a signal processor installed in a communication device. In one embodiment, the signal processor comprises a voice activity detector, a nonlinear echo processor, and a speaker attenuation module. The voice activity detector generates a control signal indicating whether both a far-end talker at a far end and a near-end talker at a near end are speaking or only the far-end talker is speaking. The nonlinear echo processor, controlled by the control signal, cancels more nonlinear echo from the near-end signal in time domain while only the far-end talker is speaking and cancels less nonlinear echo from the near-end signal in time domain while both the far-end talker and the near-end talker are speaking. The speaker attenuation module, controlled by the control signal, attenuates the far-end signal while both the far-end talker and the near-end talker are speaking.01-01-2009
20090316881TIMESTAMP QUALITY ASSESSMENT FOR ASSURING ACOUSTIC ECHO CANCELLER OPERABILITY - A voice communication end device provides echo reduction when operating in a full duplex mode using acoustic echo cancellation, which includes periodic audio queue adjustments to account for drift. The end device performs a quality assessment by calculating consistency statistics for the queue adjustments to determine whether acoustic echo cancellation would be ineffective, and if so falls back to a half duplex mode using voice switching.12-24-2009
20120195423SPEECH QUALITY ENHANCEMENT IN TELECOMMUNICATION SYSTEM - Technologies are generally described for an echo cancelling device of a telecommunication system. In some examples, an echo canceling device may include a noise reduction unit configured to reduce a background noise around a near-end talker from a near-end signal provided by a microphone, a double talk detector configured to detect a double talk event based on the noise-reduced near-end signal and a far-end signal, and a filtering unit configured to receive the far-end signal and the near-end signal provided by the microphone.08-02-2012
20100226491NOISE CANCELLATION FOR PHONE CONVERSATION - The present disclosure relates to systems and methods for noise cancellation of phone conversation. Some of the systems can include a phone having a microphone and a noise cancellation device. In some examples, the noise cancellation device has a microphone for receiving an input sound wave and positioned proximate the phone microphone, a processor for generating a noise cancellation sound wave based on the input sound wave, and a speaker for outputting the noise cancellation sound wave. The phone microphone and the noise cancellation device microphone can be shared or different microphones, and can also be microphone is integral to the phone. The shared or separate microphones can be part of a phone headset.09-09-2010
20090110185VEHICLE CALL DEVICE, CALL SYSTEM, CENTER, AND CALLING METHOD - A vehicle call device, a call system, a center, and a calling method capable of detecting a problem while controlling the cost increase are disclosed. The vehicle call device includes a speaker mounted in a vehicle, the speaker outputting a received voice of an opposite communication party; a microphone mounted in the vehicle; an echo canceller unit removing the received voice that has been output from the speaker and input into the microphone; a detecting unit detecting an emergency situation of the vehicle; and a remove preventing unit preventing the eco canceller unit from removing the received voice when the detecting unit detects the emergency situation.04-30-2009
20110243318APPARATUS AND METHOD FOR CANCELING ECHO - According to one embodiment, in response to a first acoustic signal output, a second acoustic signal is input. A filter unit is configured to generate a third acoustic signal by convoluting the first acoustic signal with coefficients. A subtraction unit is configured to generate a fourth acoustic signal by subtracting the third acoustic signal from the second acoustic signal. An estimation unit is configured to decide whether a sound volume of the first acoustic signal is below a predetermined threshold, and to set a sound volume of the second acoustic signal as a non-echo sound level when the sound volume of the first acoustic signal is below the predetermined threshold. A determination unit is configured to determine a step size to correct the coefficients using the non-echo sound level. A correction unit is configured to correct the coefficients using the step size.10-06-2011
20110069829METHODS, APPARATUS AND ARTICLES OF MANUFACTURE TO CANCEL ECHO FOR COMMUNICATION PATHS HAVING LONG BULK DELAYS - Example methods, apparatus and articles of manufacture to cancel echo for communication paths having long bulk delays are disclosed. A disclosed example method includes determining a first location of a first largest magnitude of a first plurality of coefficients of an echo canceller, the first plurality of coefficients separated by two or more sample intervals, and cancelling an echo contained in a received signal using a second plurality of coefficients of the echo canceller and a first offset selected based on the first location, the second plurality of coefficients separated by one sample interval.03-24-2011
20080219431METHOD AND APPARATUS FOR ECHO CANCELLATION - A telephony system equipped with an echo cancellation module is disclosed. A hybrid interface circuit outputs an outbound signal to a wall jack while receiving an inbound signal from the wall jack. The inbound signal may contain a line echo of the outbound signal caused by the impedance mismatches in the hybrid interface circuit. A line echo canceller containing an adaptive filter is used to cancel the line echo in the inbound signal based on the learned line echo path characteristics captured in the training period. During a brief period after the telephony system is activated, the line echo canceller enters into a calibration mode wherein its adaptive filter is trained to learn the line echo path characteristics. During the calibration mode, the line echo canceller generates a calibration signal as the outbound signal and receives the line echo from the hybrid interface circuit to perform learning of the line echo path characteristics.09-11-2008
20100195815ECHO REMOVING APPARATUS - An echo removing apparatus that can remove an echo appropriately if the produced sound volume becomes large although the configuration is simple is provided. A control section 08-05-2010
20090185674Communication system - In an embodiment, a method for removing an echo component is a first signal received at an audio input device includes outputting a second signal from an audio output device, receiving at the audio input device the first signal wherein the echo component in the first signal is the result of the second signal traversing an echo path; detecting if the first signal only comprises the echo component; determining an estimate indicative of the echo path by comparing the first signal and the second signal when it is detected that the first signal only comprises echo; applying the estimate indicative of the echo path to the first signal to determine an equalised first signal; comparing the equalised first signal with the second signal to determine an estimate indicative of the echo component; and removing the echo component from the first signal in dependence on the estimate indicative of the echo component; wherein the step of detecting if the first signal only comprises the echo component comprises comparing a characteristic of the equalised first signal to a characteristic of the second signal.07-23-2009
20120063590OPERATING POINTS FOR SPECTRUM MANAGEMENT IN DIGITAL SUBSCRIBER LINES - A method of determining a number of operating points for spectrum management of a plurality of digital subscriber lines in a communications network, the method comprising the steps of: determining optimization criteria (O03-15-2012
20120250852ACOUSTIC ECHO CANCELLATION FOR HIGH NOISE AND EXCESSIVE DOUBLE TALK - Methods and devices for improved echo cancellation in high noise environments, such as in-car speakerphones and the like, are provided that improve cancellation convergence in a high noise environment and in the presence of double talk. A new update method enables a robust echo canceller to update with reduced concern for the canceller being in a receive state or a double talk state. If a signal generated by a local talker is substantially the same as high noise, in terms of corruption of the echo canceller, the echo canceller converges in a robust manner even with continuous high noise at the input.10-04-2012
20120237017METHOD, DEVICE AND SYSTEM FOR EXTENDING CHANNELS - The present invention provides a method, a device and a system for extending channels, and belongs to the field of communications technologies. The method includes: generating a non-cascade extended channel by using a first channel and a second channel; and generating a first-level cascade extended channel by using the non-cascade extended channel and a third channel, where the first channel and the second channel are both twisted-pair channels, and the third channel is a twisted-pair channel or another non-cascade extended channel. The device includes a first transformer and a second transformer. The system includes a first device and a second device.09-20-2012
20080253552Acoustic Echo Canceller - An acoustic echo cancellation device (10-16-2008
20130177150CROSSTALK REDUCING CONDUCTOR AND CONTACT CONFIGURATION IN A COMMUNICATION SYSTEM - There is disclosed a method for reducing cross talk between first and second cables in a data transmission system, each of the cables comprised of a pair of conductors. The method comprises the steps of providing a first contact interconnected with a first conductor of the pair of conductors of the first cable, wherein the first contact emits a first signal, providing a pair of contacts, each of the pair of contacts interconnected with a different conductor of the pair of conductors of the second cable, and positioning the first contact relative to the pair of contacts such that an amplitude of the signal received at one of the second pair of contacts is substantially the same as an amplitude of the signal received at another of the second pair of contacts.07-11-2013

Patent applications in class ECHO CANCELLATION OR SUPPRESSION

Patent applications in all subclasses ECHO CANCELLATION OR SUPPRESSION