Feedback Suppression Patents (Class 381/318)
  • Patent number: 8085961
    Abstract: A hearing device and method for monitoring the hearing ability of a person with impaired hearing allow changes of the hearing ability specifically of a person wearing a hearing aid are to be better able to be registered and taken into account. For this purpose, the setting of an operating element, this serves for setting an output sound level of a hearing device. Furthermore, the ambient sound level in the vicinity of the hearing device is measured. After that, the current setting is compared with the current, measured ambient sound level and a corresponding control signal is output dependent on the result of the comparison. This control signal serves, for example, for signaling to the wearer of a hearing aid the loss of hearing or the automatic adjustment of the hearing aid.
    Type: Grant
    Filed: February 23, 2006
    Date of Patent: December 27, 2011
    Assignee: Siemens Audiologische Technik GmbH
    Inventors: Stefan Aschoff, Matthias Fröhlich
  • Patent number: 8077893
    Abstract: The aim of the invention is to provide inter-channel level differences ICLD related to audio signals for hearing aids.
    Type: Grant
    Filed: May 30, 2008
    Date of Patent: December 13, 2011
    Assignee: Ecole Polytechnique Federale de Lausanne
    Inventors: Olivier Roy, Martin Vetterli
  • Publication number: 20110293124
    Abstract: A fitting device for fitting a hearing device to compensate for a hearing loss of a user is disclosed, the hearing device comprising a receiver and a microphone, wherein a feedback path exists between the receiver and the microphone, wherein the hearing device further comprises an adaptive feedback canceller configured to reduce feedback, the adaptive feedback canceller comprising a fixed filter corresponding to an invariant portion of the feedback path, and an adaptive filter corresponding to a variant portion of the feedback path, the fitting device comprising a processor configured to determine the invariant portion of the feedback path, wherein the processor is configured to provide the fixed filter with information relating to the invariant portion of the feedback path independently of the user using the hearing device.
    Type: Application
    Filed: February 10, 2011
    Publication date: December 1, 2011
    Inventor: Guilin MA
  • Patent number: 8068629
    Abstract: A hearing aid (200) with multiple microphones comprises a first microphone (1) for converting sound into a first audio signal, a second microphone (20) for converting sound into a second audio signal, directional processing means for combining the first and said second audio signal according to a mixing ratio to form a spatial signal, estimating means for estimating a first acoustic feedback signal entering the first microphone and a second acoustic feedback signal entering the second microphone, processing means (4) for processing said spatial signal by applying a gain not exceeding a resulting maximum gain limit to form a hearing loss compensation signal, wherein the resulting maximum gain limit is derived from the first and second acoustic feedback signals and the mixing ratio, and an output transducer (3) for converting the hearing loss compensation signal into an acoustic output. The invention further provides a method and a computer program product.
    Type: Grant
    Filed: August 5, 2008
    Date of Patent: November 29, 2011
    Assignee: Widex A/S
    Inventors: Kristian Tjalfe Klinkby, Peter Magnus Norgaard, Helge Pontoppidan Foeh, Thilo Volker Thiede
  • Patent number: 8050436
    Abstract: In acoustic systems, especially with hearing aids, feedback whistling keeps occurring. To avoid this, a limit gain frequency response of the amplification device, which represents the limits of feedback whistling, is thus recorded. On the basis of the curve recorded a required gain frequency response with a number of interpolation points is created, with each interpolation point having a predetermined minimum distance in each case to the limit gain frequency response in at least two different directions. This enables feedback whistling to be largely avoided, even with shifts in resonant frequencies.
    Type: Grant
    Filed: October 31, 2005
    Date of Patent: November 1, 2011
    Assignee: Siemens Audiologische Technik GmbH
    Inventor: Robert Kasanmascheff
  • Patent number: 8045738
    Abstract: Feedback detection, adaptive notch filtering, and gain adjustment are combined for managing feedback. Feedback detection includes detection of short term and long term spectral peaks and assessing their magnitude, shape, rate of growth, and power concentration ratio. A plurality of notch filters are available and are allocated according to the spectral magnitude of the feedback detected. Wide band gain adjustment supplements the notch filters.
    Type: Grant
    Filed: October 31, 2008
    Date of Patent: October 25, 2011
    Assignee: Zounds Hearing, Inc.
    Inventor: Sandeep Prasad Sira
  • Patent number: 8045737
    Abstract: According to the invention, a real ear acoustic coupling quantity representative of the acoustic coupling of a hearing instrument to the user's ear or an anatomical transfer quantity—for example the Real-Ear-to-Coupler-Difference (RECD), the Microphone Location Effect (MLE), the Coupler Response for Flat Insertion Gain (CORFIG), and/or the Real Ear Open Gain (REOG)—is obtained from a transfer function representative of an acoustic transfer from the receiver to the outer microphone such as a signal feedback threshold gain. The obtained quantity may be used for setting a fitting parameter of the hearing instrument, for example a gain correction.
    Type: Grant
    Filed: March 1, 2006
    Date of Patent: October 25, 2011
    Assignee: Phonak AG
    Inventor: Alfred Stirnemann
  • Publication number: 20110249846
    Abstract: Disclosed herein, among other things, are methods and apparatus for allocating feedback cancellation resources for improved acoustic feedback cancellation for hearing assistance devices. In various embodiments, a hearing assistance device includes a microphone and a processor configured to receive signals from the microphone and process them according to a plurality of processing blocks. The processor is adapted to include an event detector that can provide detection of an event and an output to adjust one or more processing blocks of the overall process to more efficiently use resources of the processor for the event detected, in various embodiments.
    Type: Application
    Filed: April 12, 2011
    Publication date: October 13, 2011
    Applicant: Starkey Laboratories, Inc.
    Inventor: Harikrishna P. Natarajan
  • Publication number: 20110249847
    Abstract: Disclosed herein, among other things, are methods and apparatus for improved feedback cancellation for hearing assistance devices. In various embodiments the present acoustic feedback cancellation system is configured to identify the onset of acoustic feedback. This early detection is accomplished in a variety of ways, including detection of an exponential rise in a periodic signal which is associated with early acoustic feedback. The present system is very rapid and so it can operate when the conditions surrounding the hearing aid change quickly. It also is useful to not impose feedback cancellation to longer notes that will “fool” less sophisticated acoustic feedback cancellers into thinking the sound is feedback.
    Type: Application
    Filed: April 12, 2011
    Publication date: October 13, 2011
    Applicant: Starkey Laboratories, Inc.
    Inventors: Arthur Salvetti, Harikrishna P. Natarajan
  • Patent number: 8019104
    Abstract: A hearing aid includes an input transducer for transforming an acoustic input signal into an electrical input signal, a processor for generating an electrical output signal by amplifying the electrical input signal with a processor gain, an output transducer for transforming the electrical output signal into an acoustic output signal, an adaptive feedback suppression filter for generating a feedback cancellation signal, and a model gain estimator generating an upper processor gain limit and for providing a control parameter indicating a possible misadjustment of the model.
    Type: Grant
    Filed: June 15, 2007
    Date of Patent: September 13, 2011
    Assignee: Widex A/S
    Inventors: Kristian Tjalfe Klinkby, Helge Pontoppidan Foeh, Thilo Volker Thiede
  • Publication number: 20110211715
    Abstract: A hearing device has a signal-processing apparatus for processing an input signal into an output signal, and a feedback-canceller apparatus for reducing feedback artifacts on the basis of the input signal and the output signal. The feedback-canceller apparatus has an adaptive, first filter, for establishing a set of filter coefficients for a predefined feedback situation. The feedback-canceller apparatus is configured to store the set of filter coefficients. It has at least one second filter, which can be operated directly parallel to the first filter on the basis of the stored set of filter coefficients. The adaptive, first filter can be continuously adapted to a current feedback situation, and the feedback-canceller apparatus is configured such that in the current feedback situation it automatically selects either the first or the second filter. As a result, it generally only requires a simple switchover, but not a complete adaptation.
    Type: Application
    Filed: February 28, 2011
    Publication date: September 1, 2011
    Applicant: SIEMENS MEDICAL INSTRUMENTS PTE. LTD.
    Inventors: Sebastian Pape, Stefan Petrausch, Tobias Wurzbacher
  • Patent number: 8005247
    Abstract: The hearing aid system has a sound-to-vibration conversion circuitry including a microphone system, an electronic amplifier and a vibrator. A housing accommodates the vibrator. The vibrator is connected to an abutment that goes through the skin. The abutment is connected to a fixture that is anchored in the skull bone. The sound-to-vibration conversion circuitry has an A/D converter that converts an analogue microphone signal into a digital signal.
    Type: Grant
    Filed: November 11, 2006
    Date of Patent: August 23, 2011
    Assignee: Oticon A/S
    Inventor: Patrik Westerkull
  • Publication number: 20110194714
    Abstract: A hearing device has a feedback suppression unit. The hearing device further has a low-pass filter characterized by a first cut-off frequency, which couples out a low-frequency signal component from an output signal of the hearing device, and a high-pass filter characterized by a second cut-off frequency, which couples out a high-frequency signal component from the output signal of the hearing device. A frequency shift unit shifts the frequency of the high-frequency signal component to higher frequencies. A gap exists between the first and the second cut-off frequency. As a result of the different limit frequencies, signal distortions caused by frequency shifts are effectively suppressed. Feedback is suppressed continuously and rapidly at higher frequencies.
    Type: Application
    Filed: January 28, 2011
    Publication date: August 11, 2011
    Applicant: SIEMENS MEDICAL INSTRUMENTS PTE. LTD.
    Inventor: Henning Puder
  • Publication number: 20110194715
    Abstract: Feedback in a hearing device and, more particularly, in a hearing aid should be compensated for before it becomes audible. To this end, a method is proposed for compensating for a feedback signal in a hearing device with an input-transducer apparatus, a signal-processing apparatus and an output-transducer apparatus, in which method a feedback signal is compensated for, which feedback signal is fed back to the input-transducer apparatus from the output-transducer apparatus or the signal-processing apparatus. More particularly, a probability of having a plurality of notches, equally spaced apart from one another, in the spectrum of an input signal is established, which input signal originates directly from the input-transducer apparatus or which is a difference signal between the signal directly from the input-transducer apparatus and a compensation signal serving for compensation. The compensation is modified or the signal-processing apparatus is amplified as a function of this established probability.
    Type: Application
    Filed: February 9, 2011
    Publication date: August 11, 2011
    Applicant: SIEMENS MEDICAL INSTRUMENTS PTE. LTD.
    Inventors: SEBASTIAN PAPE, STEFAN PETRAUSCH
  • Patent number: 7995780
    Abstract: A hearing aid includes a hearing aid housing enclosing a microphone for converting sound into an audio signal, first feedback compensation means for providing a first feedback compensation signal of signals picked up by the microphone by modeling an internal mechanical feedback signal path of the hearing aid, second feedback compensation means for providing a second feedback compensation signal by modeling an external feedback signal path of the hearing aid, subtracting means for subtracting the first and second feedback compensation signals from the audio signal to form a compensated audio signal, processing means, connected to an output of the subtracting means, for processing the compensated audio signal, and a receiver, connected to an output of the processing means, for converting the processed compensated audio signal into a sound signal.
    Type: Grant
    Filed: August 18, 2006
    Date of Patent: August 9, 2011
    Assignee: GN ReSound A/S
    Inventors: Brian Dam Pedersen, Erik Lindberg
  • Publication number: 20110188685
    Abstract: A method for detecting whistling in an audio system includes determining an average frequency of an input signal of the audio system, sampling the input signal in consecutive blocks of at least one sample, wherein the average frequency is determined blockwise, and determining whether feedback related whistling is present in the input signal of the audio system by evaluating a stability of the average frequency, wherein the evaluation of the stability of the average frequency comprises: determining a difference of two values of the determined average frequency for two blocks, and comparing the determined difference to a first threshold value.
    Type: Application
    Filed: December 29, 2010
    Publication date: August 4, 2011
    Inventor: Naim SHEIKH
  • Publication number: 20110188686
    Abstract: A hearing device (HD) incorporates a method for adaptive cancellation of acoustic feedback (AF). The method comprises generating an estimated feedback signal (EF) and subtracting the estimated feedback signal (EF) from the microphone signal (MS) before feeding it to a signal processor (SP) providing the primary hearing device function. The estimated feedback signal (EF) is generated in an adaptive filter (FE1), which is controlled using a least-mean-square algorithm, which operates on an error signal (E) and a reference signal (R). The algorithm may behave erroneously if the feedback path changes while a signal with low HF content, such as speech, is received. In this case, the hearing device (HD) will not be able to quickly adapt the HF characteristic of the adaptive filter (FE1) to the changed conditions. The adaptive filter (FE1) may thus have an incorrect HF gain when a subsequent signal with high HF content is received.
    Type: Application
    Filed: January 28, 2011
    Publication date: August 4, 2011
    Inventor: Steen Michael Munk
  • Patent number: 7983433
    Abstract: Disclosed is an earset assembly that has a housing having a microphone port and a speaker port. A microphone is enclosed by the housing and has first and second input ports. The first input port is acoustically coupled to the microphone port to detect air pressure changes of the ear of a user. A speaker is enclosed by the housing and has an output port acoustically coupled to the speaker port to broadcast sounds to the user. The output port is acoustically coupled to the second input port of the microphone so that the microphone cancels at least a portion of feedback from the sounds broadcast by the speaker and detected at the first input port of the microphone.
    Type: Grant
    Filed: November 8, 2006
    Date of Patent: July 19, 2011
    Assignee: Think-A-Move, Ltd.
    Inventor: Guerman G. Nemirovski
  • Patent number: 7978861
    Abstract: A method for continuously monitoring noise exposure level of a person via measuring sound level within an ear canal of the person using a sound measurement means linked to a sound level recording device external to the ear canal, wherein the sound measurement means may be shielded from the environment by a hearing protective device, and wherein the cable does not interfere with the ability of the hearing protective device to reduce noise exposure level in the ear canal. Also provided are a system comprising a sound measurement means mounted within an ear canal of the person, an external sound level recording means and a linking cable.
    Type: Grant
    Filed: May 17, 2005
    Date of Patent: July 12, 2011
    Assignee: Sperian Hearing Protection, LLC
    Inventor: Kevin Michael
  • Patent number: 7974428
    Abstract: A hearing aid having an input transducer (2), a signal processor (3), an output transducer (4) and an adaptive filter (5) for generating a feedback cancellation signal (101) further comprises a norm estimator (10) generating a first norm signal (109) indicative of a norm of the electrical input signal and a second norm signal (110) indicative of a norm of a feedback-cancelled electrical input signal, a comparator for comparing the first and second norm signals and generating a difference value Nfbc?Nx and a decision unit disabling application of the feedback cancellation signal to the signal path of the hearing aid if the difference value is above a certain threshold value cth thus avoiding the feedback cancellation mechanism actually increasing acoustic feedback of the hearing aid. The invention also provides a method for reducing acoustic feedback of a hearing aid, a computer program, and an electronic circuit for a hearing aid.
    Type: Grant
    Filed: February 17, 2006
    Date of Patent: July 5, 2011
    Assignee: WIDEX A/S
    Inventors: Tjalfe Kristian Klinkby, Thilo Volker Thiede
  • Publication number: 20110150231
    Abstract: The present disclosure relates to tracking of acoustic feedback events of a hearing assistance device, such as a hearing aid. Information about the acoustic feedback events is stored for analysis. Such information is useful for programming acoustic feedback cancellers and other parameters of a hearing assistance device.
    Type: Application
    Filed: December 22, 2009
    Publication date: June 23, 2011
    Applicant: Starkey Laboratories, Inc.
    Inventor: Harikrishna P. Natarajan
  • Publication number: 20110150257
    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.
    Type: Application
    Filed: April 2, 2009
    Publication date: June 23, 2011
    Applicant: Oticon A/S
    Inventors: Jesper Jensen, Thomas Bo Elmedyb
  • Patent number: 7965853
    Abstract: An improved method for adaptively cancelling acoustic feedback in hearing aids and other audio amplification devices. Feedback cancellation is limited to a frequency band that encompasses all unstable frequencies. By limiting the bandwidth of the feedback cancellation signal, the distortion due to the adaptive filter is minimized and limited only to the unstable feedback regions. A relatively simple signal processing algorithm is used to produce highly effective results with minimal signal distortion.
    Type: Grant
    Filed: November 5, 2007
    Date of Patent: June 21, 2011
    Assignee: House Research Institute
    Inventors: Shawn X. Gao, Sigfrid D. Soli, Hsiang Feg Chi
  • Patent number: 7965854
    Abstract: An improved method for adaptively cancelling acoustic feedback in hearing aids and other audio amplification devices. Feedback cancellation is limited to a frequency band that encompasses all unstable frequencies. By limiting the bandwidth of the feedback cancellation signal, the distortion due to the adaptive filter is minimized and limited only to the unstable feedback regions. A relatively simple signal processing algorithm is used to produce highly effective results with minimal signal distortion.
    Type: Grant
    Filed: November 5, 2007
    Date of Patent: June 21, 2011
    Assignee: House Research Institute
    Inventors: Shawn X. Gao, Sigfrid D. Soli, Hsiang-Feg Chi
  • Patent number: 7949144
    Abstract: There is provided a method for monitoring a hearing device having an electroacoustic output transducer worn at a user's ear or in a user's ear canal, the method includes the steps of measuring the electrical impedance of the output transducer; analyzing the measured electrical impedance of the output transducer in order to evaluate the status of the output transducer and/or of an acoustical system cooperating with the output transducer; and outputting a status signal representative of the status of the output transducer and/or of the acoustical system cooperating with the output transducer.
    Type: Grant
    Filed: June 12, 2006
    Date of Patent: May 24, 2011
    Assignee: Phonak AG
    Inventors: Samuel Harsch, Evert Dijkstra
  • Publication number: 20110116667
    Abstract: A system providing method and apparatus to detect occurrence of an entrainment artifact and address it. The system analyzing a feedback canceller filter for certain characteristics that are associated with an entrained filter. When an entrained filter is detected, the feedback canceller filter is reset to a good filter that ideally represents the current approximate external acoustic feedback path without the characteristics of the entraining signal.
    Type: Application
    Filed: September 3, 2010
    Publication date: May 19, 2011
    Applicant: Starkey Laboratories, Inc.
    Inventors: Harikrishna P. Natarajan, Jon S. Kindred
  • Patent number: 7945066
    Abstract: A hearing assistance system having adjustable bulk delay for cancellation of a time varying acoustic feedback path. The hearing assistance system including an FIR filter, coefficient update module, and delay rules module for programmable adaptive filtering. The hearing assistance system adjustable for continuous bulk delay adjustments. The hearing assistance system providing a number of coefficient update routines, including, but not limited to an LMS coefficient update process and a normalized LMS coefficient update process.
    Type: Grant
    Filed: June 9, 2008
    Date of Patent: May 17, 2011
    Assignee: Starkey Laboratories, Inc.
    Inventor: Jon S. Kindred
  • Patent number: 7945057
    Abstract: A procedure and device for linearizing the characteristic curve of a vibration signal transducer such as a microphone that includes collecting signals, transmitting the signals, extracting information from the signals, dephasing such information by 180 degrees compared to the initial signals and taking the algebraic sum of the initial signals and dephased information.
    Type: Grant
    Filed: February 27, 2006
    Date of Patent: May 17, 2011
    Assignee: Ferdos Innovations LLC
    Inventor: Samad F. Pakzad
  • Patent number: 7933424
    Abstract: A hearing aid comprises an input transducer (2), a subtraction node for subtracting a feedback cancellation signal from the electrical input signal thereby generating a processor input signal, a signal processor (3), an output transducer (4), a pair of equalization filters (7a, 7b) for selecting from the processor input and output signals a plurality of frequency band signals, a frequency equalization unit for frequency equalization for the selected frequency band signals, and an adaptive feedback estimation filter (5, 6) for adaptively deriving the feedback cancellation signal from the equalized frequency band signals. The equalization of selected frequency bands of the input signals of the adaptive feedback cancellation filter provides for an improved and in particular a faster adaption of the feedback cancellation. The invention further provides a method of reducing acoustic feedback of a hearing aid, and a hearing aid circuit.
    Type: Grant
    Filed: September 1, 2006
    Date of Patent: April 26, 2011
    Assignee: Widex A/S
    Inventors: Kristian Tjalfe Klinkby, Peter Magnus Norgaard, Jorgen Cederberg
  • Patent number: 7925031
    Abstract: The invention concerns an audio system comprising a microphone, audio signal processing means, an output transducer and mans 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, mans are provided for changing the phase of the audio signal at a given frequency.
    Type: Grant
    Filed: April 25, 2006
    Date of Patent: April 12, 2011
    Assignee: Oticon A/S
    Inventors: Thomas Bo Elmedyb, Johan Hellgren
  • Publication number: 20110026746
    Abstract: A method for determining feedback thresholds in a plurality of frequency bands and/or at a plurality of frequencies processed by a hearing device is disclosed. The feedback thresholds are defined as gains, at which feedback occurs while a hearing device user is wearing the hearing device. The method comprises the steps of determining a quality index for a measured feedback threshold, and considering a measured feedback threshold as final if the quality index meets minimum predefined requirements.
    Type: Application
    Filed: September 20, 2007
    Publication date: February 3, 2011
    Applicant: PHONAK AG
    Inventors: Patrick Baechler, Stefan Pislak, Andreas Von Buol, Bernd Waldmann
  • Patent number: 7876856
    Abstract: Methods and apparatus to compensate for I/Q mismatch in quadrature receivers are disclosed. An example apparatus disclosed herein comprises a correction engine using first filter coefficients to compensate for I/Q mismatch present in a received quadrature signal; an adaptation engine to adapt second filter coefficients based on I/Q mismatch present in the received quadrature signal; and coefficient controller to occasionally adjust the first filter coefficients based on the second filter coefficients.
    Type: Grant
    Filed: June 23, 2005
    Date of Patent: January 25, 2011
    Assignee: Texas Instrumentals Incorporated
    Inventors: Imtinan Elahi, Khurram Muhammad
  • Publication number: 20100329493
    Abstract: A hearing apparatus and an associated method for suppressing feedback include a microphone emitting a microphone signal and a receiver picking up a receiver signal by subtracting a compensation signal from the microphone signal. The hearing apparatus includes a number of preset static first compensation filters for forming first compensation signals from the receiver signal and a first selection unit, which selects a first compensation signal in such a way that a feedback signal caused by the feedback is minimal in the receiver signal. An advantage thereof is that adaptation artifacts cannot occur.
    Type: Application
    Filed: June 30, 2010
    Publication date: December 30, 2010
    Applicant: SIEMENS MEDICAL INSTRUMENTS PTE. LTD.
    Inventors: Georg-Erwin Arndt, Robert Bäuml, Andreas Tiefenau
  • Patent number: 7860263
    Abstract: In a hearing device with low feedback tendency with simultaneous open feed and utilization of the natural directional effect of the pinna, the hearing device has a tube-shaped ear fitting piece for insertion into an auditory canal and speaker is arranged in the ear fitting piece, and at least two microphones are arranged in the ear fitting piece acoustically-symmetrically to the speaker in the built-in state of the hearing device in the ear fitting piece. The sound emitted by the speaker that can be differentiated from the usable sound, such that the level of feedback can be reduced. At the same time, open feed and utilization of the natural directional effect of the pinna are ensured.
    Type: Grant
    Filed: July 25, 2006
    Date of Patent: December 28, 2010
    Assignee: Siemens Audiologische Technik GmbH
    Inventor: Eghart Fischer
  • Publication number: 20100310103
    Abstract: A method for determining feedback thresholds in a plurality of frequency bands and/or at a plurality of frequencies processed by a hearing device is disclosed. The feedback thresholds are defined as gains, at which feedback occurs while a hearing device user is wearing the hearing device. The method comprises the step of determining feedback thresholds in an order of precedence, wherein the order of precedence being defined according to a degree of importance that the feedback threshold is determined in a particular frequency band or at a particular frequency, respectively.
    Type: Application
    Filed: September 20, 2007
    Publication date: December 9, 2010
    Applicant: PHONAK AG
    Inventors: Patrick Baechler, Bernd Waldmann, Andreas Von Buol, Stefan Pislak
  • Patent number: 7844063
    Abstract: Hearing aids with microphone and telephone coil are to be made simpler and more convenient. For this purpose it is provided to use an adaptive filter to compensate acoustic and electromagnetic feedback. In order to allow for the propagation delay differences, a delay element is connected downstream of the telephone coil. The microphone and telephone coil signals can be individually weighted with the factors a and b so that mixed mode is also possible.
    Type: Grant
    Filed: April 25, 2006
    Date of Patent: November 30, 2010
    Assignee: Siemens Audiologische Technik GmbH
    Inventors: Volkmar Hamacher, Henning Puder
  • Publication number: 20100296680
    Abstract: A method for determining a maximum gain is disclosed that is applicable in a forward signal path starting at a microphone (1) and ending at a receiver (11) of a hearing device, the maximum gain being a gain value at which just no feedback occurs. The method comprising the steps of estimating a estimated feedback transfer function (F?) characterizing a feedback signal path (15) starting at a receiver (11) and ending at a microphone (1) of the hearing device, while the hearing device is inserted into an ear of a hearing device user, and adapting the estimated feedback transfer function (F?) as a result of a changing feedback signal path (15) by applying an adaptive algorithm. The invention is characterized by determining the maximum gain from the estimated feedback transfer function (F?), in particular by coefficients of the estimated feedback transfer function.
    Type: Application
    Filed: January 22, 2008
    Publication date: November 25, 2010
    Applicant: PHONAK AG
    Inventors: Sascha Korl, Lukas Kuhn
  • Publication number: 20100260365
    Abstract: A configuration and associated methods are used for detecting acoustic feedback in a hearing device. One embodiment contains a first feedback detection unit, which determines the probability of feedback, a second feedback detection unit, which determines a weighting factor, and an arithmetic unit, which multiplies the feedback probability by the weighting factor. As an alternative to determining the weighting factor, a threshold value may also be controlled. This offers the advantage of improved acoustic feedback detection by a combination of two different feedback detection methods.
    Type: Application
    Filed: March 22, 2010
    Publication date: October 14, 2010
    Applicant: SIEMENS MEDICAL INSTRUMENTS PTE. LTD.
    Inventor: Stefan Petrausch
  • Patent number: 7813497
    Abstract: Echo canceling method comprising the steps: a) receiving a first signal and a second signal, said second signal comprising an echo of the first signal, b) generating an echo replica signal by filtering the first signal with a finite impulse response filter, said finite impulse filter using a filter coefficient vector for generating the echo replica signal, generating an echo cancelled signal by subtracting the echo replica signal from the second signal, d) determining a measure of interference within the second signal, e) determining a step vector depending on said measure of interference, wherein increasing the measure of interference continuously reduces a size of the step vector, and f) updating the filter coefficient vector by the step vector.
    Type: Grant
    Filed: January 20, 2005
    Date of Patent: October 12, 2010
    Assignee: ST-Ericsson SA
    Inventor: Wolfgang Brox
  • Publication number: 20100254555
    Abstract: The invention relates to a hearing aid system with an electrical feedback cancellation path, for compensating acoustic feedback between an output transducer and an input transducer by subtracting an estimate of the acoustical feedback from a signal on the input side of the amplifier part, the electrical feedback cancellation path comprising an adaptive filter for providing a variable filtering function. The invention further relates to a method of compensating acoustic feedback in a hearing aid system and to its use. The object of the present invention is to provide an alternative scheme for estimating the acoustical/mechanical feedback in a hearing aid. The problem is solved in that the hearing aid system comprises a second electrical input signal consisting essentially of the direct part of said first electrical input signal (i.e.
    Type: Application
    Filed: September 30, 2008
    Publication date: October 7, 2010
    Applicant: OTICON A/S
    Inventors: Thomas Bo Elmedyb, Johan Hellgren
  • Patent number: 7809150
    Abstract: A system providing method and apparatus to detect occurrence of an entrainment artifact and address it. The system analyzing a feedback canceller filter for certain characteristics that are associated with an entrained filter. When an entrained filter is detected, the feedback canceller filter is reset to a good filter that ideally represents the current approximate external acoustic feedback path without the characteristics of the entraining signal.
    Type: Grant
    Filed: May 27, 2004
    Date of Patent: October 5, 2010
    Assignee: Starkey Laboratories, Inc.
    Inventors: Harikrishna P. Natarajan, Jon S. Kindred
  • Publication number: 20100246868
    Abstract: The goal is to make insertion of a hearing apparatus in an ear more comfortable, in particular with respect to feedback whistling. A method for operating a hearing apparatus by amplifying an input sound to form an output sound and compensating by a predefined amount for feedback caused by the output sound is therefore provided. In a predetermined period after switching on the hearing apparatus, the amount of feedback compensation is automatically increased by an offset greater than zero compared with the predefined amount. By way of example, amplified feedback, which is caused by a hand when inserting the hearing apparatus or hearing aid into the ear, can be better compensated thereby. Feedback whistling when inserting a hearing aid for example can thus be avoided.
    Type: Application
    Filed: March 19, 2010
    Publication date: September 30, 2010
    Applicant: SIEMENS MEDICAL INSTRUMENTS PTE. LTD.
    Inventor: Ulrich Kornagel
  • Patent number: 7801318
    Abstract: With a hearing aid device, filter parameters of filters are to be adjusted for feedback suppression. It is hereby proposed that test signals are emitted via an earpiece in order to estimate the transmission behavior of the feedback path, and response signals to these test signals are recorded by a microphone and analyzed in the hearing aid device. In this way, information signals which are already occasionally emitted by the hearing aid device and can be perceived by the user are used as test signals. Information signals of this type are particularly well suited as test signals and are perceived by the user as non-interfering.
    Type: Grant
    Filed: May 25, 2006
    Date of Patent: September 21, 2010
    Assignee: Siemens Audiologisch Technik GmbH
    Inventor: Roland Barthel
  • Publication number: 20100232634
    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.
    Type: Application
    Filed: June 4, 2008
    Publication date: September 16, 2010
    Applicant: OTICON A/S
    Inventor: Jesper Bünsow Boldt
  • Publication number: 20100232632
    Abstract: According to various embodiment of a method of operating a hearing instrument, an acoustic signal pathway is provided from a microphone through a signal processor to a hearing instrument (HI) receiver in an acoustic mode of operation. An RF transmit signal pathway is provided from the microphone to an RF transmitter, and an RF receive signal pathway is provided from the RF receiver through the signal processor to the HI receiver in an RF mode of operation. An input signal representative of sound detected by the microphone is adaptively filtered. A first adaptation rate is used for the acoustic mode of operation and a second adaptation rate is used for the RF mode of operation. The second adaptation rate is faster than the first adaptation rate.
    Type: Application
    Filed: March 12, 2009
    Publication date: September 16, 2010
    Inventors: Jon S. Kindred, Jeffrey Paul Solum
  • Publication number: 20100226516
    Abstract: A method for operating a hearing apparatus includes determining feedback events, in which feedback suppression responds and/or in which feedback is detected above a predeterminable feedback threshold value, determining a frequency of the feedback events within a predeterminable duration and emitting a signal if the determined frequency exceeds a predeterminable frequency threshold value. A time instant for changing an earmold which is no longer optimally positioned and is the cause of a frequent feedback can therefore be advantageously predicted in a timely manner. A computer program product for implementing the method and a hearing apparatus with acoustic feedback suppression and/or acoustic feedback identification, are also provided.
    Type: Application
    Filed: March 8, 2010
    Publication date: September 9, 2010
    Applicant: SIEMENS MEDICAL INSTRUMENTS PTE. LTD.
    Inventors: Alexander Grafenberg, Johannes Lauer
  • Publication number: 20100208924
    Abstract: The hearing aid system (102) has a sound-to-vibration conversion circuitry including a microphone system (108), an electronic amplifier (114) and a vibrator (120). A housing (121) accommodates the vibrator (120). The vibrator (120) is connected to an abutment (124) that goes through the skin. The abutment (124) is connected to a fixture (126) that is anchored in the skull bone (128). The sound-to-vibration conversion circuitry has an AfD converter (212) that converts an analogue microphone signal into a digital signal.
    Type: Application
    Filed: November 11, 2006
    Publication date: August 19, 2010
    Applicant: OTICON A/S
    Inventor: Patrik Westerkull
  • Publication number: 20100202641
    Abstract: This invention relates to a hearing device for compensating hearing impairment of a user. The hearing device comprises an input signal converter for converting an acoustic signal to an electric signal, a signal processor, an output signal converter for converting a processed signal to a processed acoustic signal presented to the user, and an adaptive feedback suppression unit compensating for acoustic feedback between the output signal converter and the input signal converter and to generate a feedback compensation signal, which is mixed with the electric signal from the input signal converter to provide a compensated electric signal. The signal processor is adapted to process the compensated electric signal and to generate a processed signal therefrom.
    Type: Application
    Filed: February 5, 2010
    Publication date: August 12, 2010
    Applicant: OTICON A/S
    Inventor: Meng GUO
  • Publication number: 20100177917
    Abstract: A hearing aid includes a signal processor, a input transducer electrically connected to the signal processor, a receiver electrically connected to the signal processor, an adaptive feedback cancellation filter configured to suppress feedback from a signal path between the receiver and the input transducer, and a feedback gain correction unit configured for adjusting a gain parameter of the signal processor based at least in part on coefficients of the adaptive feedback cancellation filter. A method of adjusting a gain parameter of a signal processor of a hearing aid includes monitoring filter coefficients of a feedback cancellation filter of the hearing aid, and adjusting the gain parameter of the signal processor in dependence of the monitored filter coefficients.
    Type: Application
    Filed: January 13, 2009
    Publication date: July 15, 2010
    Applicant: GN RESOUND A/S
    Inventor: Erik Cornelis Diederik VAN DER WERF
  • Patent number: RE42935
    Abstract: Estimates of spectral magnitude and phase are obtained by an estimation process using spectral information from analysis filter banks such as the Modified Discrete Cosine Transform. The estimation process may be implemented by convolution-like operations with impulse responses. Portions of the impulse responses may be selected for use in the convolution-like operations to trade off between computational complexity and estimation accuracy. Mathematical derivations of analytical expressions for filter structures and impulse responses are disclosed.
    Type: Grant
    Filed: December 21, 2007
    Date of Patent: November 15, 2011
    Assignee: Dolby Laboratories Licensing Corporation
    Inventors: Corey I. Cheng, Michael J. Smithers, David N. Lathrop