Abstract: Techniques are provided for reduction of echo in a received audio signal based on infinite impulse response (IIR) acoustic echo cancellation in the frequency domain. A methodology implementing the techniques according to an embodiment includes estimating an echo path transfer function associated with the received audio signal. The received audio signal includes a combination of a speech signal and a reference signal modified by the echo path transfer function. The estimation employs an IIR filter and a finite impulse response (FIR) filter, both of which operate in the frequency domain. The IIR filter is configured to model longer term echo components and the FIR filter is configured to model shorter term echo components. The method further includes applying the filters to the reference signal to generate an echo correction signal which is subtracted from the received audio signal to reduce the echo and generate an estimate of the speech signal.

Abstract: An audio processing apparatus and an audio processing method are provided. The audio processing apparatus includes a microphone array, a processor, and an audio signal processor. The microphone array is configured to provide an external audio signal having a first sampling frequency. The external audio signal includes a first audio signal and a second audio signal. The processor provides a first setting command and a second setting command according to the external audio signal and the second audio signal. The audio signal processor generates the second audio signal having a second sampling frequency according to the first setting command, adjusts the second sampling frequency of the second audio signal to the first sampling frequency according to the second setting command, and separates the first audio signal in the external audio signal according to the second audio signal having the first sampling frequency.

Abstract: Disclosed is an echo canceller including: a false echo calculator that calculates false echo signals by performing a filtering operation using each of current and previous filter-coefficient groups which used by an adaptive filtering unit on a sequence of reception signals (x(n)); an evaluation value calculator that calculates evaluated values of an echo cancellation quantity on the basis of a voice-transmission signal (y(n)) and the false echo signals; a false echo selector that selects an estimated echo component from the false echo components on the basis of the evaluated values of the echo cancellation quantity; and a signal output unit (Sout) that outputs a residual signal (e(n)).

Abstract: Techniques for adaptive noise cancellation for multiple audio endpoints in a shared space are described. According to one example, a method includes detecting, by a first audio endpoint, one or more audio endpoints co-located with the first audio endpoint at a first location. A selected audio endpoint of the one or more audio endpoints is identified as a target noise source. The method includes obtaining, from the selected audio endpoint, a loudspeaker reference signal associated with a loudspeaker of the selected audio endpoint and removing the loudspeaker reference signal from a microphone signal associated with a microphone of the first audio endpoint. The method also includes providing the microphone signal from the first audio endpoint to at least one of a voice user interface (VUI) or a second audio endpoint, wherein the second audio endpoint is located remotely from the first location.

Abstract: Embodiments disclosed herein provide systems, methods, and computer readable media for synchronizing algorithmic state data with audio trace signals. In a particular embodiment, a method provides processing digital audio data linearly in the time domain using a digital audio processing algorithm. The method further provides determining the digital algorithmic state data comprising an output state of the digital audio processing algorithm at each of a plurality of time instances during the processing of the digital audio data. Also, the method provides aligning the digital algorithmic state data in the time domain with a trace of the digital audio data.

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.

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.

Abstract: The present invention relates to an arrangement for point-to-point transmission over links between first and second link (end) terminals in a system implementing time division duplex (TDD) and wherein information is sent over the links in frames divided into time slots. It is adapted to determine the lengths of the frames on a per link basis using one or more link parameters, the frame length hence being variable.

Abstract: Systems and methods for characterizing loops based on frequency domain reflectometry single-ended line testing (FDR-SELT) are described. One embodiment includes a method for determining whether a straight-loop departure condition exists on a loop under test. First, an un-calibrated echo signal is received. A region associated with the loop under test, a platform type, and estimated the length of the loop under test are then used together with the received un-calibrated echo signal to determine whether the loop is not a straight loop is determined through determining whether at least one differentiating feature is present in the received signal. Another embodiment includes a method for determining a loop gauge for a loop under test through analyzing characteristics relating to local maxima and local minima of the received un-calibrated echo signal using the region, platform type, and the estimated loop length.

Abstract: An integrated hybrid circuit includes a transmission unit, a transceiver coil, a transceiver circuit, a hybrid matching circuit, and a receiving circuit. The transmission unit generates a pair of upstream signals according to a user transmission signal. The transceiver coil transmits the pair of upstream signals to a central office through a pair of twisted pair, and receiving a pair of downstream signals from the central office through the pair of twisted pair. The hybrid matching circuit receives an adjustment signal to adjust selective impedances. The receiving circuit receives the pair of downstream signals from the central office, and generates the adjustment signal according to downstream and upstream rates and signals from the hybrid matching circuit. The transmission unit adjusts transmission power and bandwidth of the transmission unit and the receiving unit adjusts filter bandwidth of the receiving unit according to the adjustment signal for optimizing upstream and downstream rates.

Abstract: Methods and systems monitoring performance of acoustic echo cancellation are described. An audio output is generated by applying a first acoustic echo cancellation algorithm to an audio input. One or more performance metrics for the first acoustic echo cancellation algorithm based on the audio output are determined via a second acoustic echo cancellation algorithm. The first acoustic echo cancellation algorithm is different from the second acoustic echo cancellation algorithm. The one or more performance metrics are provided for storage in a memory.

Abstract: Method, arrangement and devices for calibration of a line driving device, such as a DSLAM, having a line port. The method comprises deriving of a first parameter vector, PVinf, for example Hinf. The parameter vector PVinf is derived by performing, at a first site, an echo measurement on the line driving device while the line port on said line driving device is open. The method further comprises calibrating the line driving device based on the first parameter vector PVinf and a second parameter vector PVref, which second parameter vector is based on information on echo measurements performed on at least one reference line driving device.

Abstract: An improper connection determination method includes a closed circuit forming step, a current detection step and a determination step. In the closed circuit forming step, a closed circuit from one of at least two contacts in a telephone connection terminal of a communication apparatus to another one of the at least two contacts in the telephone connection terminal is formed. In the current detection step, a current flowing in the closed circuit, when the closed circuit is formed in the closed circuit forming step, is detected. In the determination step, it is determined that the telephone line is improperly connected to the telephone connection terminal when the current is detected in the current detection step.

Abstract: A system and method in accordance with a non-limiting aspect minimizes echo return loss in a communications system. The dial tone is broken on an analog telephone line connected to a hybrid circuit having selectable impedance configurations and that interfaces a digital communications circuit and the analog telephone line. A white noise signal as a test call is inserted through the hybrid circuit onto the analog telephone line corresponding to a selected impedance configuration. The returned white noise signal is used for measuring the echo return loss. The test call is dropped. This process is repeated at different impedance configurations to obtain echo return loss measurements at each of the impedance configurations. The optimum impedance setting configuration is determined based on the results and applied to the hybrid circuit and typically set during a running telephone configuration.

Abstract: Architecture that employs a signal (e.g., audible or inaudible sounds) to detect if endpoints of a communications session are sufficiently close to each other to induce echo, and then control (e.g., muting) is applied to one or more of the endpoints to prevent echo. The signals can be played and detected from the endpoints or a central conferencing component such as a multiple control unit (MCU). The MCU can provide support for legacy endpoints as well. When echo is detected, the offending endpoint(s) can be controlled to mute one or more onboard devices such as a speaker or microphone. The device(s) can be muted from a remote component or for a local component or locally by the endpoint user. A notification can be sent that notifies the endpoint user that the mute operation has been applied or should be applied to one or more of the local devices.

Abstract: A multimedia conferencing system includes a loud speaker system, one or more microphones for receiving a local audio signal and a remote audio signal, a state machine and an echo canceller that operates in conjunction with two reference signals to remove substantially all of a feedback signal component in the local audio signal that results from reinforcing and playing the local audio signal over the loud speaker system. The state machine operates to detect that only the local audio is active, and if so controls the operation of the echo canceller such that only the feedback component of the local audio signal is removed and the local audio signal is not suppressed.

Abstract: A method and apparatus for providing echo cancellation are disclosed. For example, the method receives via an echo canceller a first audio signal directed towards an endpoint device, and adds an inserted signal to the first audio signal directed towards the endpoint device. The method determines if a second audio signal being received from the endpoint device comprises the inserted signal, and cancels at least a portion of the second audio signal that is associated with the first audio signal, if the inserted signal is detected.

Abstract: A system, method, and program product are provided for filtering sound from a selected application on a computer without interrupting voice communications on the computer. The method comprises: monitoring a selected program for an outgoing digital audio signal from a selected application; detecting said digital audio signal; and filtering an analog microphone input with the digital audio signal.

Abstract: Echo cancellation is handled using a pattern classification technique. During a training phase, the communications device is trained to learn patterns of signal inputs that correspond to certain communication modes. After numerous different patterns have been classified by mode, the classified patterns are used during real-time use of the communications device in order to determine, dynamically, the mode in which the communications device is currently operating. The communications device may then apply, to the microphone-produced signal, a suppression action.

Abstract: An embodiment of a method and apparatus for determining a change in network-generated crosstalk levels caused by a multi-line phone includes determining a first crosstalk level between a first line pair and a second line pair of a multi-line phone caused by the multi-line phone, and determining a second crosstalk level between each of the first line pair and the second line pair of the multi-line phone. The second crosstalk level is determined when the first line pair and the second line pair are coupled to a first predetermined length of network line pair cable. The method further includes determining a change of network generated crosstalk levels caused by the multi-line phone by subtracting the first crosstalk level from the second crosstalk level.

Abstract: Test equipment including a signal generator and a method of generating a test signal associated with an overall frequency band are disclosed. Also disclosed is a method of using the test signal to test an echo canceller. The method of generating the test signal includes generating a first time segment associated with a first frequency sub-band of the overall frequency band and generating a second time segment associated with a second frequency sub-band of the overall frequency band. The second frequency sub-band is higher than the first frequency sub-band. The method further includes generating a time gap segment separating the first time segment and the second time segment.

Abstract: Integrated echo cancellers in a telecommunications system are tested using a test apparatus connected to the main communications trunk where a large number of individual signals are multiplexed together. The signals are de-multiplexed in the test apparatus and specific amounts of echo delay, echo magnitude, and line delay can be introduced for any selected signals within the group on the trunk. The signals are then re-multiplexed and returned to the trunk in a direction back toward the echo canceller.

Abstract: A second output transmission signal (“TX2”) added to a line driver is a scaled version of the main output transmission signal (“TX1”). TX2 is scaled from TX1 by a variable scale factor K. An adaptive hybrid circuit subtracts TX1 and TX2 from a line signal carrying both a line transmission signal and a line received signal (“RX”). A programmable impedance Ztune is coupled between the TX2 output of the line driver and the RX output of the adaptive hybrid circuit. A transmission echo in the output RX signal is measured. K and Ztune are then adaptively tuned to minimize the transmission echo. The hybrid in this case becomes a 4-port network, one port specifically added to adaptively cancel the transmission echo in the RX output of the adaptive hybrid circuit. Alternatively, the hybrid may be a 3-port hybrid including variable impedances to cancel the line transmission signal.

Abstract: 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.

Abstract: An apparatus to enable half-duplexing capabilities in a two-way communication device is disclosed. The apparatus estimates the signal power and background noise of a first input signal and a second input signal during approximately the same period. The apparatus further provides at least one control signal based on the result of one or more determinations. These determinations may include whether the estimated signal power of at least one of the first and second input signals exceeds a threshold value; whether the estimated signal power of the first input signal exceeds the sum of a first threshold value and the estimated background noise of the first input signal; and whether the estimated signal power of the second input signal exceeds the sum of a second threshold value and the estimated background noise of the second input signal. Other embodiments for use with two-way communication devices and related methods are also disclosed.

Abstract: Described is automatically testing the quality of an audio coupling between juxtaposed first and second digital telephones, e.g., VoIP telephones, such as to quantitatively determine the quality of audio echo cancellers in those digital telephones. An analyzer receives timestamps from a first telephone and second telephone during a calling session, including timestamps for when the second telephone initially provides audio (e.g., speech) to the first telephone, when the first telephone initially detects sound, when the first telephone initially provides audio to the second telephone, and when the second telephone initially detects sound. The analyzer uses the relative timing of the timestamps and the speech recognizer's outcome to determine whether the audio coupling is experiencing interference or echo. When the audio includes speech, a confidence level corresponding to accuracy of speech recognition also may establish the audio coupling's quality.

Abstract: An echo canceller (106) can include a first multi-band filter (152) which receives a first input signal (108) and generates a first plurality of sub-band signals (110, 111, 112), and a second multi-band filter (154) which receives a second input signal (122) and generates a second plurality of sub-band signals (156, 157, 158). The echo canceller also can include a plurality of double talk detectors (168, 169, 170) that each generate a double talk flag (182, 183, 184) based on at least a respective one of the first sub-band signals and a respective one of the second sub-band signals.

Abstract: Disclosed is an echo suppresser or cancellation circuit including a speech signal extrapolation unit. The speech extrapolation unit may provide extrapolated signal segment approximations to an echo segment replacement unit. The echo segment replacement unit may replace a segment of a first speech signal suspected of being corrupted with an echo component of a second signal using the extrapolated signal segment approximated to represent the corrupted signal segment.

Abstract: An echo canceller comprising a first adaptive filter having N_long coefficients for converging to an echo path, a non-adaptive filter representing a direct echo path portion captured by the first adaptive filter and having N_short default coefficients, where N_long>N_short, for quick convergence of the echo canceller at start-up, wherein the default coefficients are replaced by the first N_short coefficients from the first adaptive filter responsive to an improvement in echo return loss enhancement (ERLE) of the first adaptive filter, a second adaptive filter having N_short default coefficients for modeling the direct echo path and providing an indication of double-talk and echo path changes, decision logic for receiving error signal outputs from the first and second adaptive filters and the non-adaptive filter and in response distinguishing between echo path changes and double-talk, and a non-linear processor for attenuating signals responsive to input from the decision logic.

Abstract: There are provided methods and systems for automated testing of echo cancellers using natural speech excitations and evaluating an echo canceller by transmitting a first signal to the echo canceller, wherein the first signal includes a first speech signal and a first marker signal, and wherein the first marker signal is transmitted a first period of time after the first speech signal is transmitted; receiving a second signal from the echo canceller, wherein the second signal includes a second speech signal and a second marker signal; aligning the first speech signal and the second speech signal using the first marker signal and the second marker signal; determining a choppiness of the second speech signal, when a non-linear processor of the echo canceller is on; and determining an audible echo, when a non-linear processor of the echo canceller is off.

Abstract: A wireless communications system is provided with reduced sideband noise and carrier leakage. In the system, at least one transmitter modulates at least one input signal with a first carrier to generate a modulated output signal, and at least one receiver receives the modulated output signal and demodulates the same with a second carrier to generate at least one demodulated output signal. The first and second carriers are at different frequencies, such that the sideband noise and carrier leakage generated by different sources can be distinguished.

Abstract: An apparatus to enable half-duplexing capabilities in a two-way communication device is disclosed. The apparatus estimates the signal power and background noise of a first input signal and a second input signal during approximately the same period. The apparatus further provides at least one control signal based on the result of one or more determinations. These determinations may include whether the estimated signal power of at least one of the first and second input signals exceeds a threshold value; whether the estimated signal power of the first input signal exceeds the sum of a first threshold value and the estimated background noise of the first input signal; and whether the estimated signal power of the second input signal exceeds the sum of a second threshold value and the estimated background noise of the second input signal. Other embodiments for use with two-way communication devices and related methods are also disclosed.

Abstract: Bidirectional differential point to point simultaneous high speed signalling is provided between integrated circuits with highly effective echo canceling. Each integrated circuit comprises a transmitter for transmitting a first signal to another integrated circuit and a receiver for receiving a second signal from the other integrated circuit. The transmitter has an output buffer; a receiver has a receiver buffer and is co-located on the same integrated circuit; and a differential buffer is coupled between the input of the transmitter buffer and the output of the receiver buffer. To increase the quality of receiving the second signal, a third signal adjusted in phase and amplitude is coupled at the output of the receive buffer, so that the echoing of the first signal is canceled. Preferably, the rise time of the third signal is also adjusted.

Abstract: A method and system for performing diagnostic tests on a communications system. Diagnostic test signals are generated by a transceiver included within the communications system. Diagnostic data signals generated within the communications system in response to the diagnostic test signals are collected by the transceiver. The communications transceiver may operate alone, with an assisting communications transceiver, or with a non-assisting communications transceiver. The collected diagnostic data signals are stored and made available for later analysis. The method and system are used to generate and store ECHO Crosstalk, Near End Cross Talk (NEXT) and Far End CrossTalk (FEXT) data signals.

Abstract: An embodiment of a method and apparatus for determining a change in network-generated crosstalk levels caused by a multi-line phone includes determining a first crosstalk level between a first line pair and a second line pair of a multi-line phone caused by the multi-line phone, and determining a second crosstalk level between each of the first line pair and the second line pair of the multi-line phone. The second crosstalk level is determined when the first line pair and the second line pair are coupled to a first predetermined length of network line pair cable. The method further includes determining a change of network generated crosstalk levels caused by the multi-line phone by subtracting the first crosstalk level from the second crosstalk level.

Abstract: Testing equipment for and a method of performance testing an echo canceller are disclosed. The method includes generating a white noise test signal that includes a plurality of high-level white noise time segments, each of which is separated by a low-level white noise time gap. The generated white noise test signal is transmitted to the echo canceller. At least one echo output signal is received from the echo canceller, and the echo output signal results from the white noise test signal. The level and duration of the received at least one echo output signal are measured.

Abstract: Techniques for simultaneously and efficiently eliminating echo and noise mixed in voice are disclosed. According to one aspect of the present invention, an adaptive filter system for eliminating noises and echo mixed in voice signal comprises a first signal adaptive filter, a first subtractor, a second adaptive filter and a second subtractor. The first signal adaptive filter estimates the noise mixed in the voice signal according to a reference noise. The first subtractor subtracts the noise estimated by the first adaptive filter from the voice signal to obtain a voice signal without the mixed noise. The second adaptive filter estimates the echo mixed in the voice signal according to a remote voice signal. The second subtractor subtracts the echo estimated by the second adaptive filter from the voice signal without mixed noise to obtain a clean voice signal.

Abstract: A method and apparatus are disclosed for reducing cross-talk in an unbalanced channel with a reduced number of redundancies. A cross-talk canceller is disclosed that uses a multi-dimensional finite impulse response (FIR) filter to process a received signal. Redundancies are reduced or even removed entirely by processing the signals received on each twisted pair in a vector form, using multi-dimensional finite impulse response filters. The signals received by a transceiver on each twisted pair are represented in a vector form so that the signals received on each twisted pair, and the cross-talk effect that each signal has on one another, can be performed collectively. A multi-dimensional cross-talk canceller processes a vector representation of the corresponding signals transmitted by the transceiver on each twisted pair.

Abstract: A fault associated with a communication medium is analyzed by correlating a first set of information indicative of echo associated with the communication medium with a second set of information indicative of echo. The fault is characterized based on the correlation between the first set of information and the second set of information. The first set of information and the second set of information can include echo canceller coefficients generated by an echo canceller coupled to the communication medium.

Abstract: Systems and methods for performing loop length estimation are described. One embodiment includes a method which comprises receiving an echo signal for a loop under test where the echo signal is a per-port calibrated echo response obtained using frequency domain reflectometry single-ended line testing (FDR-SELT). The method further comprises analyzing characteristics of the echo signal to perform a loop length estimation based on data relating to ripple frequency as a function of loop length.

Abstract: Systems and methods for performing loop gauge detection are described. One embodiment is a method that comprises receiving a calibrated per-port echo signal of a loop under test, receiving a loop length estimation for the loop under test, and estimating the loop gauge of the loop under test if the loop is not determined to be a long loop based on a predetermined threshold and if no bridge tap is present on the loop. In accordance with such embodiments, estimating the loop gauge of the loop under test is based on at least one of the following echo signal features: energy of the echo signal in a predetermined frequency band, information on an envelope of maxima for the echo signal, information on an envelope of minima for the echo signal, and a span of ripples on the amplitude of the echo signal.

Abstract: A testing and performance analysis methodology applies a series of test vector pairs to the input ports of an echo canceller under test. The test vector signal pair may represent a particular speech activity state transition, e.g., a Brady Model transition. A scoring compression function such as a sigmoid squashing function is used to evaluate quantized performance parameters. The sub-scores may be weighted and averaged to provide an overall performance score.

Abstract: A duplexer for a communication device having a transmission unit, a reception unit and a shared antenna is disclosed. The duplexer comprises a first signal path between the transmission unit and the reception unit, the first signal path comprises a filter unit filtering the reception signal, the filtering unit provides a filtered signal to the reception unit. The duplexer further comprises a second signal path between the transmission unit and the reception unit. The second signal path comprises a cancellation unit which receives a sample of the transmission signal and produces a compensation signal. The injection of the compensation signal to the first signal path reduces the leakage signal, thereby producing a substantially leakage-free reception signal.

Abstract: A hybrid circuit within a full-duplex transceiver transmits an outgoing signal outward on a communication channel at the same time it receives an incoming signal arriving via the communication channel, and the outgoing and incoming signals sum to form a combined signal. The hybrid circuit generates both the outgoing signal and a replica of the outgoing signal in response to an input signal, and then subtracts the replica from the combined signal in producing a received signal. The received signal includes a component derived from the incoming signal and a residual echo component having peaks resulting from a phase difference between the outgoing signal and its replica. The transceiver adjustably delays the input signal so that the residual echo component peaks occur at times other then when the received signal is being digitized, thereby minimizing the influence of the echo component peaks on the data sequence.

Abstract: A fault associated with a communication medium is analyzed by correlating a first set of information indicative of echo associated with the communication medium with a second set of information indicative of echo. The fault is characterized based on the correlation between the first set of information and the second set of information. The first set of information and the second set of information can include echo canceller coefficients generated by an echo canceller coupled to the communication medium.

Abstract: An echo cancelling system comprises a system controller for directing inbound and outbound PCM signals to one of two echo canceller modules. The system controller receives status information from the echo cancellers and maintains state information pertaining to the active echo canceller, in order to allow seamless switchover from one echo canceller to the other without interrupting service.

Abstract: Integrated echo cancellers in a telecommunications system are tested using a test apparatus connected to the main communications trunk where a large number of individual signals are multiplexed together. The signals are de-multiplexed in the test apparatus and specific amounts of echo delay, echo magnitude, and line delay can be introduced for any selected signals within the group on the trunk. The signals are then re-multiplexed and returned to the trunk in a direction back toward the echo canceller.

Abstract: A method and system for performing diagnostic tests on a communications system. Diagnostic test signals are generated by a transceiver included within the communications system. Diagnostic data signals generated within the communications system in response to the diagnostic test signals are collected by the transceiver. The communications transceiver may operate alone, with an assisting communications transceiver, or with a non-assisting communications transceiver. The collected diagnostic data signals are stored and made available for later analysis. The method and system are used to generate and store ECHO Crosstalk, Near End Cross Talk (NEXT) and Far End CrossTalk (FEXT) data signals.

Abstract: In a modem pool system capable of mitigating alien crosstalk, a system including a first modem pool including at least two modems, at least one protected line connected to one of the modems, at least one sensor line connected to another of the modems, at least one alien crosstalk predictor operative to sample an alien signal on the at least one sensor line and provide an alien crosstalk prediction signal, and at least one alien crosstalk prediction summation element operative to receive the alien crosstalk prediction signal from the alien crosstalk predictor and subtract the alien crosstalk prediction signal from a data transmission signal on the protected line.

Abstract: Techniques for adaptive noise cancellation for multiple audio endpoints in a shared space are described. According to one example, a method includes detecting, by a first audio endpoint, one or more audio endpoints co-located with the first audio endpoint at a first location. A selected audio endpoint of the one or more audio endpoints is identified as a target noise source. The method includes obtaining, from the selected audio endpoint, a loudspeaker reference signal associated with a loudspeaker of the selected audio endpoint and removing the loudspeaker reference signal from a microphone signal associated with a microphone of the first audio endpoint. The method also includes providing the microphone signal from the first audio endpoint to at least one of a voice user interface (VUI) or a second audio endpoint, wherein the second audio endpoint is located remotely from the first location.