Abstract: A listening device includes an input transducer, an output transducer, a signal processor, and a feedback cancellation system for estimating acoustic feedback. The feedback cancellation system includes an adaptive FBC filter arranged in parallel to the forward path, an adaptive whitening filter, and a howl detection unit that performs howl detection based on an output of the adaptive whitening filter. The adaptive FBC filter includes a variable FBC filter part and an FBC update algorithm part for updating the variable FBC filter part, the FBC update algorithm part receiving first and second FBC algorithm input signals influenced by the electrical input and the electrical output signals. Further, the feedback cancellation system receives an electrical update signal essentially consisting of the direct part of the electrical input signal and coefficients of the adaptive whitening filter are based on the electrical update signal.

Abstract: A method and an audio processing system determine a system parameter, e.g. step size, in an adaptive algorithm, e.g. an adaptive feedback cancellation algorithm so as to provide an alternative scheme for feedback estimation in a multi-microphone audio processing system. A feedback part of the system's open loop transfer function is estimated and separated in a transient part and a steady state part, which can be used to control the adaptation rate of the adaptive feedback cancellation algorithm by adjusting the system parameter, e.g. step size parameter, of the algorithm when desired system properties, such as a steady state value or a convergence rate of the feedback, are given/desired. The method can be used for different adaptation algorithms such as LMS, NLMS, RLS, etc. in hearing aids, headsets, handsfree telephone systems, teleconferencing systems, public address systems, etc.

Abstract: A listening device system includes two listening devices, each having its own separate housing. The first device includes an input transducer housed within the housing for converting an input sound to an electrical input signal which includes a direct and an acoustic feedback part, and a feedback cancellation system. The feedback cancellation system includes an adaptive FBC filter including a variable FBC filter part, and an FBC update algorithm part for updating the variable FBC filter part. The FBC update algorithm part receives first and second input signals influenced by the electrical input and the electrical output signals. The second listening device includes an input transducer housed within its housing producing an electrical update signal essentially consisting of the direct part of said electrical input signal. The update signal is conveyed from the second device to the first device, where feedback cancellation parameters are adjusted based on that signal.

Abstract: A hearing aid system includes an input transducer, an output transducer, and an electrical signal path between them. The signal path includes a signal processing unit. An electrical feedback cancellation path is formed between the output side and the input side of the signal path and subtracts an estimate of acoustical feedback from a signal on the input side of the amplifier part, the electrical feedback cancellation path including an adaptive filter for providing a variable filtering function. A probe signal generator generates a probe signal characterizing an acoustical feedback path, the probe signal being fed to the adaptive filter of the electrical feedback cancellation path. A second input transducer is located at a position where the acoustical signal is substantially free from acoustic feedback from the output transducer, and the adaptive filter uses a signal derived from the second electrical input signal to influence its filtering function.

Abstract: Disclosed is a method of reducing feedback in a hearing aid adapted to be worn by a user, the method comprising the step of: receiving an audio input signal in an input transducer in the hearing aid; wherein the method further comprises the steps of: transforming the input signal into the frequency domain; dividing the audio signal into a plurality of frequency bands; determining a threshold frequency over which a plurality of upper frequency bands lies; multiplying each of the plurality of upper frequency bands by a random phase, thereby obtaining a plurality of phase randomized upper frequency bands; synthesizing the plurality of phase randomized upper frequency bands and the lower frequency bands to an output signal; transforming the output signal into the time-domain; and transmitting the output signal to an output transducer of the hearing aid.

Abstract: A hearing aid system may include an ear-mould for a child, an output transducer, and an electrical feedback path. A forward path includes a signal processor that modifies an electrical input signal to a specific hearing profile over a predefined frequency range which includes a number of frequency bands. Maximum forward gain values IGmax for each band are stored in a memory, restricting loop gain to a predetermined value in each band. The hearing aid system further includes a relatively slow online feedback manager unit configured to, with a predefined update frequency, identify current feedback gain in each frequency band, and to subsequently adapt the maximum forward gain values IGmax in each of the frequency bands in accordance with a predefined scheme. The feedback manager unit is thus reduces the risk of howling by decreasing the maximum forward gain values IGmax in said ear-mould for a child.

Abstract: The invention relates to a hearing aid system comprising first and second spatially separated hearing instruments, the system being adapted for processing input sounds to output sounds according to a user's needs. The invention further relates to a method and use. The object of the present invention is to provide an alternative scheme for reducing the effect of acoustic feedback in a hearing aid system.

Abstract: The invention regards a scheme for generating a probe noise signal to be used in an anti feedback system of an audio system. The audio system comprises e.g. a microphone for capturing an audio signal, an audio signal processor for adaptation of the audio signal and a receiver for generation of an audible signal. According to an embodiment of the invention, a noise signal is injected into the audio signal path between the microphone and the receiver and used for estimating acoustical feedback, the noise signal being generated by the following steps: converting a digitized audio signal to the frequency domain, in order to obtain a series of magnitude and phase values, changing the phase values such that the phase of the resulting signal becomes less correlated, preferably substantially un-correlated, to the original signal, converting the magnitude and phase back to a time domain signal using the changed phase values. The invention may e.g. be used in a hearing aid, a headset or a pair of headphones.

Abstract: The invention relates to a hearing aid system comprising an input transducer, a forward path, an output transducer and an electrical feedback path, the forward path comprising a signal processing unit for modifying an electrical input signal to a specific hearing profile over a predefined frequency range, wherein the predefined frequency range comprises a number of frequency bands, for which maximum forward gain values IGmax for each band can be stored in a memory, the electrical feedback path comprising an adaptive filter for estimating acoustical feedback from the output to the input transducer. The invention further relates to a method of adapting a hearing aid system to varying acoustical input signals. The object of the present invention is to provide an alternative acoustic feedback compensation scheme.

Abstract: The invention concerns in a first aspect an audio system comprising a microphone, audio signal processing means, an output transducer and means for detecting a possible feedback tone and the corresponding frequency of the feedback tone in the audio system between the output transducer and the microphone. According to the invention means for counteracting feedback are provided. Further, means are provided for changing the phase of the audio signal at a given frequency. In a further aspect, a binaural hearing aid system comprising first and second hearing instruments according to the first aspect, each hearing instrument comprising transceiver circuitry allowing an exchange of signals between the two hearing instruments, and wherein the binaural hearing aid system is adapted to provide that a phase change introduced in the first audio signal by a controller of the first hearing instrument is or can be introduced in the second audio signal of the second hearing instrument via said transceiver circuitry.

Abstract: An audio processing system processing an input sound to an output sound includes: an input transducer for converting input sound to an electric input signal and defining an input side; an output transducer for converting a processed electric output signal to an output sound and defining an output side; a forward path defined between the input transducer and the output transducer; a signal processing unit for processing an SPU-input signal originating from the electric input signal and to provide a processed SPU-output signal, and an electric feedback loop from the output side to the input side, having a feedback path estimation unit for estimating an acoustic feedback transfer function from the output transducer to the input transducer, and a enhancement unit for estimating noise-like signal components in the electric signal of the forward path and providing a noise signal estimate output.

Abstract: A listening device includes an input and output transducers and a forward path defined between the transducers. The forward path may include a signal processing unit processing an SPU-input signal originating from the electric input signal in a time-frequency representation having successive time frames each having a frequency spectrum of the signal in the time frame in question. The signal processing unit includes a spectral content modification unit to modify values of the signal of one or more regions of the frequency spectrum of a given time frame so that the modified values are less correlated to the corresponding time-frequency regions of the input signal. A feedback path estimation unit is uses he improved processed output signal in the feedback estimation. The spectral content modification unit may base the modification on a model of the human auditory system so that the modifications are not perceptible by the user.

Abstract: A method of estimating acoustic feedback in a hearing instrument in order to reduce the impact of tonal components of acoustic feedback. The hearing instrument comprises an input transducer, an output transducer, a forward path being defined between the input transducer and the output transducer, a signal processing unit defining an input side and an output side of the forward path, and a feedback loop from the output side to the input side. The feedback loop comprises a feedback path estimation unit receiving first and second estimation input signals from the input and output side of the forward path, respectively, wherein the first and second estimation input signal paths comprise first and second long term prediction filters P(z), the feedback cancellation system being adapted to provide that the variable parameters of at least one of the long term prediction filters are estimated based on the filter input signal.

Abstract: The invention relates to a hearing instrument for processing an input sound to an output sound according to a user's needs. The invention further relates to a method of operating a hearing instrument and to use of a hearing instrument. The object of the present invention is to provide an alternative scheme for handling acoustic feedback in a hearing instrument.

Abstract: Disclosed is method of generating an audible signal in a hearing aid by estimating a weighting function of received audio signals, the hearing aid is adapted to be worn by a user; the method comprises the steps of: estimating a directional signal by estimating a weighted sum of two or more microphone signals from two or more microphones, where a first microphone of the two or more microphones is a front microphone, and where a second microphone of the two or more microphones is a rear microphone; estimating a direction-dependent time-frequency gain, and synthesizing an output signal; wherein estimating the direction-dependent time-frequency gain comprises: obtaining at least two directional signals each containing a time-frequency representation of a target signal and a noise signal; and where a first of the directional signals is defined as a front aiming signal, and where a second of the directional signals is defined as a rear aiming signal; using the time-frequency representation of the target signal an

Abstract: The invention relates to an audio processing system for processing an input sound to an output sound. The invention further relates to a method of estimating a feedback transfer function in an audio processing system. The object of the present invention is to provide an alternative scheme for minimizing feedback in audio processing systems.

Abstract: A method and an audio processing system determine a system parameter, e.g. step size, in an adaptive algorithm, e.g. an adaptive feedback cancellation algorithm so as to provide an alternative scheme for feedback estimation in a multi-microphone audio processing system. A feedback part of the system's open loop transfer function is estimated and separated in a transient part and a steady state part, which can be used to control the adaptation rate of the adaptive feedback cancellation algorithm by adjusting the system parameter, e.g. step size parameter, of the algorithm when desired system properties, such as a steady state value or a convergence rate of the feedback, are given/desired. The method can be used for different adaptation algorithms such as LMS, NLMS, RLS, etc. in hearing aids, headsets, handsfree telephone systems, teleconferencing systems, public address systems, etc.

Abstract: A method, device and system enhance an audio signal in a receiving device. The method comprises acoustically propagating a target signal from an acoustic source along an acoustic propagation path, providing a propagated acoustic signal at the receiving device; converting the received propagated acoustic signal to a propagated electric signal, the received propagated acoustic signal comprising the target signal, noise and possible other sounds from the environment as modified by the propagation path from the acoustic source to the receiving device; wirelessly transmitting a signal comprising the target audio signal to the receiving device; receiving the wirelessly transmitted signal in the receiving device; retrieving a streamed target audio signal from the wirelessly received signal comprising the target audio signal; and estimating the target signal from the propagated electric signal and the streamed target audio signal using an adaptive system.

Abstract: A listening device for processing an input sound to an output sound, includes an input transducer for converting an input sound to an electric input signal, an output transducer for converting a processed electric output signal to an output sound, a forward path being defined between the input transducer and the output transducer and including a signal processing unit for processing an input signal in a number of frequency bands and an SBS unit for performing spectral band substitution from one frequency band to another and providing an SBS-processed output signal, and an LG-estimator unit for estimating loop gain in each frequency band thereby identifying plus-bands having an estimated loop gain according to a plus-criterion and minus-bands having an estimated loop gain according to a minus-criterion.

Abstract: The invention concerns in a first aspect an audio system comprising a microphone, audio signal processing means, an output transducer and means for detecting a possible feedback tone and the corresponding frequency of the feedback tone in the audio system between the output transducer and the microphone. According to the invention means for counteracting feedback are provided. Further, means are provided for changing the phase of the audio signal at a given frequency. In a further aspect, a binaural hearing aid system comprising first and second hearing instruments according to the first aspect, each hearing instrument comprising transceiver circuitry allowing an exchange of signals between the two hearing instruments, and wherein the binaural hearing aid system is adapted to provide that a phase change introduced in the first audio signal by a controller of the first hearing instrument is or can be introduced in the second audio signal of the second hearing instrument via said transceiver circuitry.