Abstract: A method for improving voice quality is provided herein. The method includes receiving acoustic signals from a microphone array; receiving sensor signals from an accelerometer sensor of the headset; generating, by a beamformer, a speech output signal and a noise output signal according to the acoustic signals; best-estimating the speech output signal according to the sensor signals to generate a best-estimated signal; and generating a mixed signal according to the speech output signal and the best-estimated signal.

Abstract: A method for improving voice quality is provided herein. The method includes receiving acoustic signals from a microphone array; receiving sensor signals from an accelerometer sensor of the headset; generating, by a beamformer, a speech output signal and a noise output signal according to the acoustic signals; best-estimating the speech output signal according to the sensor signals to generate a best-estimated signal; and generating a mixed signal according to the speech output signal and the best-estimated signal.

Abstract: A device for acoustic echo cancellation includes a modulator, a speaker, a microphone, a demodulator, and an adaptive filter. The modulator duplicates a far-end signal to a frequency range that is higher than the far-end signal to be a first frequency-shifted signal and generates a modulated signal according to the far-end signal and the first frequency-shifted signal. The speaker generates a sound signal according to the modulated signal. The microphone generates a microphone signal according to a near-end signal and an echo signal. The echo signal is a convolution of the sound signal with a room impulse response. The demodulator extracts a demodulated signal and an echo-reference signal from the microphone signal. The adaptive filter generates a recovered signal to recover the near-end signal according to the demodulated signal and the echo-reference signal.

Abstract: A device for acoustic echo cancellation includes a modulator, a speaker, a microphone, a demodulator, and an adaptive filter. The modulator duplicates a far-end signal to a frequency range that is higher than the far-end signal to be a first frequency-shifted signal and generates a modulated signal according to the far-end signal and the first frequency-shifted signal. The speaker generates a sound signal according to the modulated signal. The microphone generates a microphone signal according to a near-end signal and an echo signal. The echo signal is a convolution of the sound signal with a room impulse response. The demodulator extracts a demodulated signal and an echo-reference signal from the microphone signal. The adaptive filter generates a recovered signal to recover the near-end signal according to the demodulated signal and the echo-reference signal.

Abstract: A sound identification device is provided. The sound identification device includes a microphone array and a processing unit. The microphone array includes a plurality of microphones disposed within a microphone module mounted on a housing of the sound identification device. Each microphone receives an acoustic signal caused by a gesture performed on a surface of the microphone module and converts the received acoustic signal to a digital acoustic signal. The processing unit is configured to receive the digital acoustic signal from each microphone, and perform a sound identification process on the digital acoustic signal from each microphone to generate a sound identification result conveying information of the gesture. The processing unit controls at least one application program executed by the processing unit according to the sound identification result.

Abstract: An acoustic capture device includes an acoustic transducer, an acoustic detector, an analog-to-digital converter, and a processing element. The acoustic transducer captures an acoustic wave to generate an analog signal. The acoustic detector detects, according to the analog signal, a specific event to generate a trigger signal. The analog-to-digital converter converts the analog signal to generate a digital signal. The processing element receives the trigger signal to execute a control process. The control process includes: analyzing the digital signal to determine ambient information; determining a first set of parameters of the acoustic detector according to the ambient information; performing a control information protocol to adjust the acoustic detector according to the first set of parameters; and performing, according to the ambient information, an enhancement processing on the digital signal to generate an enhanced digital signal.

Abstract: An acoustic capture device includes an acoustic transducer, an acoustic detector, an analog-to-digital converter, and a processing element. The acoustic transducer captures an acoustic wave to generate an analog signal. The acoustic detector detects, according to the analog signal, a specific event to generate a trigger signal. The analog-to-digital converter converts the analog signal to generate a digital signal. The processing element receives the trigger signal to execute a control process. The control process includes: analyzing the digital signal to determine ambient information; determining a first set of parameters of the acoustic detector according to the ambient information; performing a control information protocol to adjust the acoustic detector according to the first set of parameters; and performing, according to the ambient information, an enhancement processing on the digital signal to generate an enhanced digital signal.

Abstract: An audio device and a method thereof are provided. The method is adopted by an audio device to detect a voice, wherein the audio device is coupled to a host device. The method includes an acoustic conversion circuit converting an acoustic wave into an analog audio signal; an analog-to-digital converter (ADC) converting the analog audio signal into digital audio data; a first-level voice detection circuit detecting voice activity in the analog audio signal; a second-level voice detection circuit detecting a beginning syllable of a key phrase in the digital audio data when the voice activity is detected in the digital audio data; and a third-level voice detection circuit detecting the key phrase from the digital audio data only when the beginning syllable of the key phrase is detected in the digital audio data.

Abstract: An audio device and a method thereof are provided. The method is adopted by an audio device to detect a voice, wherein the audio device is coupled to a host device. The method includes an acoustic conversion circuit converting an acoustic wave into an analog audio signal; an analog-to-digital converter (ADC) converting the analog audio signal into digital audio data; a first-level voice detection circuit detecting voice activity in the analog audio signal; a second-level voice detection circuit detecting a beginning syllable of a key phrase in the digital audio data when the voice activity is detected in the digital audio data; and a third-level voice detection circuit detecting the key phrase from the digital audio data only when the beginning syllable of the key phrase is detected in the digital audio data.

Abstract: An audio apparatus is provided. The audio apparatus includes at most one electroacoustic transducer; and an audio controller, coupled to the electroacoustic transducer, for actively controlling the electroacoustic transducer to function as a loudspeaker or a microphone, wherein the loudspeaker converts output electrical signals to output sounds, and the microphone converts input sounds to input electrical signals.

Abstract: A microphone array is provided. The microphone array is disposed on an electrical device, and includes: at least one built-in microphone, being built in the electrical device, having a first frequency spectrum; and an audio processor, coupled to the built-in microphone, for coupling to an external transducer, including: a spectrum estimation unit for estimating a second frequency spectrum of the external transducer.

Abstract: An audio apparatus is provided. The audio apparatus includes at most one electroacoustic transducer; and an audio controller, coupled to the electroacoustic transducer, for actively controlling the electroacoustic transducer to function as a loudspeaker or a microphone, wherein the loudspeaker converts output electrical signals to output sounds, and the microphone converts input sounds to input electrical signals.

Abstract: An embodiment of an acoustic echo cancellation system is disclosed. The system comprises an echo cancellation unit, a second filter and a subtraction unit. The echo cancellation unit comprises a first attenuator, a first filter and a first subtractor. The first attenuator has a first down-scaling factor for attenuating a first signal. The first filter generates a first echo signal estimate based on the attenuated first signal. The first subtractor generates a third signal by subtracting the first echo signal estimate from a second signal. The second filter generates a second echo signal estimate based on the first signal. The subtraction unit subtracts the second echo signal estimate from the third signal.

Abstract: A telephone system comprising an analog telephone and a full-duplex speakerphone adapter is disclosed. The analog telephone comprises an ordinary analog telephone subscriber circuit for transmitting and receiving analog signals and a handset for users. The full-duplex speakerphone adapter is coupled between the analog telephone and a central office, uses a subscriber loop interface circuit through the first telephone line to couple to the ordinary analog telephone subscriber circuit of the analog telephone and uses a telephone hybrid interface circuit through the second telephone line to couple to a wall jack to communicate with the central office.

Abstract: A voice communication device with an integrated framework structure for echo cancellation and noise reduction is disclosed. A microphone receives a local input signal while a speaker is outputting a local output signal. The local input signal and output signal are all decomposed into a plurality of subband signals by filter banks for conducting individual processing of echo cancellation and noise reduction per subband. The subband echo canceller is followed by a DFT unit to split the cancellation result into a plurality of narrow frequency bins whereby the noise reduction is performed. The noise reduction results are recombined by an IDFT unit for residual echo removal in a subband non-linear processor. The final output is obtained from a synthesis filter bank that synthesizes the subband signals after echo cancellation and noise reduction into a full-band signal.

Abstract: 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.

Abstract: A voice communication device with an integrated framework structure for echo cancellation and noise reduction is disclosed. A microphone receives a local input signal while a speaker is outputting a local output signal. The local input signal and output signal are all decomposed into a plurality of subband signals by filter banks for conducting individual processing of echo cancellation and noise reduction per subband. The subband echo canceller is followed by a DFT unit to split the cancellation result into a plurality of narrow frequency bins whereby the noise reduction is performed. The noise reduction results are recombined by an IDFT unit for residual echo removal in a subband non-linear processor. The final output is obtained from a synthesis filter bank that synthesizes the subband signals after echo cancellation and noise reduction into a full-band signal.

Abstract: A telephone system comprising an analog telephone and a full-duplex speakerphone adapter is disclosed. The analog telephone comprises an ordinary analog telephone subscriber circuit for transmitting and receiving analog signals and a handset for users. The full-duplex speakerphone adapter is coupled between the analog telephone and a central office, uses a subscriber loop interface circuit through the first telephone line to couple to the ordinary analog telephone subscriber circuit of the analog telephone and uses a telephone hybrid interface circuit through the second telephone line to couple to a wall jack to communicate with the central office.

Abstract: An embodiment of an acoustic echo cancellation system is disclosed. The system comprises an echo cancellation unit, a second filter and a subtraction unit. The echo cancellation unit comprises a first attenuator, a first filter and a first subtractor. The first attenuator has a first down-scaling factor for attenuating a first signal. The first filter generates a first echo signal estimate based on the attenuated first signal. The first subtractor generates a third signal by subtracting the first echo signal estimate from a second signal. The second filter generates a second echo signal estimate based on the first signal. The subtraction unit subtracts the second echo signal estimate from the third signal.

Abstract: This invention deals with an adaptive echo cancelling system for communication networks. The system includes an adaptive filter for acoustic echo cancellation that uses a combination of echo cancelling and gain control techniques. The main advantages of the combination of these approaches are good communication quality during double talk and easier control of the output echo level.