Nuance Communications, Inc.

Harman Becker Automotive Systems Gmbh

Cerence Operating Company

Svox Ag

Bernd Iser

Gerhard Uwe Schmidt

Arthur Wolf

Tim Haulick

Mohamed Krini

Tobias Herbig

Meik Pfeffinger

Gerhard Nüssle

Mathias Roder

Gerhard Nuessle

Gerhard Schmidt

Patrick Hannon

Methods and apparatus for a communication system having microphones and loudspeakers to determine a noise and speech level estimate for a transformed signal, determine a SNR from the noise and speech level estimates, and determine a gain for the transformed signal to achieve a selected SNR range at a given position. In one embodiment, the gain is determined by adapting an actual gain to follow a target gain, wherein the target gain is adjusted to achieve the selected SNR range.

Methods and apparatus for adaptive gain control in a communication system

Embodiments of the present invention exploit redundancy of succeeding FFT spectra and use this redundancy for computing interpolated temporal supporting points. An analysis filter bank converts overlapped sequences of an audio (ex. loudspeaker) signal from a time domain to a frequency domain to obtain a time series of short-time loudspeaker spectra. An interpolator temporally interpolates this time series. The interpolation is fed to an echo canceller, which computes an estimated echo spectrum. A microphone analysis filter bank converts overlapped sequences of an audio microphone signal from the time domain to the frequency domain to obtain a time series of short-time microphone spectra. The estimated echo spectrum is subtracted from the microphone spectrum. Further signal enhancement (filtration) may be applied. A synthesis filter bank converts the filtered microphone spectra to the time domain to generate an echo compensated audio microphone signal. Computational complexity of signal processing systems can, therefore, be reduced.

Temporal interpolation of adjacent spectra

The present invention relates to a signal processing system, comprising a number of microphones and loudspeakers, a hands-free set configured to receive a telephone signal from a remote party and to transmit a microphone signal supplied by at least one of the microphones to the remote party; an in-vehicle communication system configured to receive a microphone signal supplied by at least one of the microphones; receive the telephone signal; amplify the microphone signal to obtain at least one first output signal; output the at least one first output signal and/or a second output signal corresponding to the telephone signal to at least one of the loudspeakers; and wherein the signal processing systems is configured to detect speech activity in the telephone signal and to control the in-vehicle communication system to reduce amplification of the microphone signal by a damping factor, if it is detected that speech activity is present in the telephone signal.

Hands-free telephony and in-vehicle communication

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.

Gain and spectral shape adjustment in audio signal processing

A noise attenuation system attenuates noise in an input signal. The system may estimate a power of the input signal, and determine a noise power value based on the input power estimate. The noise power value corresponds to an estimate of a noise power within the input signal. The system may determine an attenuation factor based on the noise power value, and attenuate the input signal by using the attenuation factor.

System for attenuating noise in an input signal

A codebook spectral envelope may be used to extend the bandwidth of a bandwidth limited signal. A system includes codebooks that list codebook spectral envelopes. A codebook spectral envelope may be selected based on a characteristic of the spectral envelope of the bandwidth limited signal. Modifications of selected codebook spectral envelopes may generate a bandwidth extension signal that may be added to the bandwidth limited signal to improve the quality of the signal.

Providing a codebook for bandwidth extension of an acoustic signal

A bandwidth extension system extends the bandwidth of an acoustic signal. By shifting a portion of the signal by a frequency value, the system generates an upper bandwidth extension signal. An extended bandwidth acoustic signal may be generated from the acoustic signal, the upper bandwidth extension signal, and/or a lower bandwidth extension signal.

System for providing an acoustic signal with extended bandwidth

A method for extending the spectral bandwidth of an excitation signal of a speech signal includes determining a bandwidth limited excitation signal of the speech signal, and applying a nonlinear function to the excitation signal for generating a bandwidth extended excitation signal.

Method for extending the spectral bandwidth of a speech signal

A system for use in providing a wideband signal from a received narrowband signal is set forth. The system comprises an extracted narrowband feature vector that corresponds to at least one characteristic of the narrowband signal. A narrowband codebook having one or more narrowband codebook index vectors is also employed, where each narrowband codebook index vector is associated with one or more corresponding narrowband codebook parameters. An analyzer is provided to correlate the extracted narrowband feature vector with an entry in the narrowband codebook. More particularly, the analyzer is responsive to the extracted narrowband feature vector to identify the narrowband codebook feature index vector that best matches the extracted narrowband feature vector. A signal mapper is provided to execute a mapping function of the extracted narrowband feature vector and/or the narrowband codebook index vector identified by the analyzer. In executing the mapping function, the signal mapper uses mapping parameters that correspond to the narrowband codebook entry associated with the narrowband codebook index vector identified by the analyzer. The signal mapper generates at least one estimated wideband feature vector through execution of the mapping function. The estimated wideband feature vector is used by a signal generator to generate a wideband signal that corresponds to an extended bandwidth version of the received narrowband signal.

System for generating a wideband signal from a received narrowband signal

A system is provided for extending the spectral bandwidth of a bandwidth limited audio signal by applying a nonlinear function to the bandwidth limited speech signal to generate the low frequency audio signal components that were attenuated in the bandwidth limited audio signal.

System and method for extending spectral bandwidth of an audio signal

An electronic communication system is set forth that includes the transmission of a narrowband speech signal corresponding to a narrowband version of speech utterances of a speaker as well as the transmission of speaker-dependent data. The speaker-dependent data may be used to correlate narrowband versions of the speech utterances of the speaker with corresponding wideband versions of the speech utterances of the speaker. Both the narrowband speech signal and the speaker-dependent data are received by a receiving party. A receiver at the receiving party uses the narrowband speech signal and the speaker-dependent data to generate a wideband speech signal corresponding to a wideband version of the speech utterances of the speaker.

System for generating a wideband signal from a narrowband signal using transmitted speaker-dependent data

A system extends a bandwidth of bandlimited audio signals by analyzing bandlimited audio signals at a transmission cycle rate. The analyzer may obtain a bandlimited parameter at a transmission cycle rate. A mapping device or logic in the system obtains a wideband parameter based on the bandlimited parameter. An audio signal generator generates a highband and/or lowband audio signal based on the wideband parameter at the transmission cycle rate. In some systems, the bandlimited audio signal is analyzed at the transmission cycle rate. The highband and/or lowband audio signals and the combined wideband audio signal are generated at the transmission cycle rate.

Growing community of inventors

Ulm, Germany

Bernd Iser