Showing papers on "Digital hearing aid published in 1996"
Patent•
27 Sep 1996
TL;DR: In this article, a detachable digital binaural processing hearing aid consisting of a DSP, two microphones, two receivers, a bi-directional communications link between each microphone/receiver and the digital signal processor, an analog-to-digital converter, and a digital-toanalog converter is presented.
Abstract: A detachable digital binaural processing hearing aid comprised of a digital signal processor (DSP), two microphones, two receivers, a bi-directional communications link between each microphone/receiver and the digital signal processor, an analog-to-digital converter, and a digital-to-analog converter. In one embodiment of the present invention, the user has the option of disabling the digital signal processor by either physically removing an external digital processing unit or by disabling a digital processor to permit an analog processor to provide audio enhancement. The user is also given the option of selecting from a variety of digital filters/compressors that generate binaural signals that are sent to both ears of the user. In a second embodiment, each hearing element comprises a digital signal processor and a communication link to the other hearing element. Two examples of the communication link are an electrical wire connecting the two hearing elements and an electromagnetic transceiving system where each hearing element has a transceiver that transmits a signal representing the sound at one ear of the user and receives a signal representing the sound at the other ear of the user.
88 citations
[...]
TL;DR: A hearing aid has at least one microphone, a digital signal conditioning stage having a signal converter, an amplifier as well as filters, and an earphone as discussed by the authors, and an analog-to-digital converter is arranged in the microphone housing.
Abstract: A hearing aid has at least one microphone, a digital signal conditioning stage having a signal converter, an amplifier as well as filters, and an earphone. For protection against emission of electromagnetic waves, an analog-to-digital converter is arranged in the microphone housing.
63 citations
Patent•
10 Dec 1996
TL;DR: In this paper, a sound pressure level was calculated for a user having difficulty in hearing and the result of word clear degree examination and the gain of digital data was used to output a sound easy to hear for the user by calculating the sound pressure levels with which the sound can be heard most clearly for a person having difficulty hearing.
Abstract: PROBLEM TO BE SOLVED: To output a sound easy to hear for a user by calculating the a sound pressure level, with which the sound can be heard most clearly for a person having difficulty in hearing, found from the hearing data of person having difficulty in hearing and the result of word clear degree examination and the gain of digital data. SOLUTION: The hearing characteristics of user and person having no difficulty in hearing are stored in a storage means 107 and the range of sound pressure for hearing sounds most clearly for the user is stored in a storage means 111 for gain calculation previously from a fitting device 109 to a hearing aid 100. The input data of input means 102 are analyzed by an analytic means 103 and power is calculated for each frequency band and sent to a control means 105. As a result of analysis of input data, the amplification factor is determined for each frequency band by the control means 105 and sent to a hearing compensating means 104. The hearing compensating means 104, where the input data from the input means 102 and the data of amplification factor are provided, performs hearing compensation and sends data to an output means 106. Then, they are outputted as sounds from an earphone 108.
8 citations
Patent•
11 Mar 1996TL;DR: The hearing aid has a processor, a program memory containing executable programs for controlling the signal processing, and a unit for input/output of data as mentioned in this paper, which is used for hearing aid.
Abstract: The hearing aid has a processor, a program memory containing executable programs for controlling the signal processing, and a unit for input/output of data. A monitoring element (1) determines a failure or interference of the loaded program. An activation element (2) automatically performs a new start of the program when the monitoring element detects the failure. The monitoring element pref. also monitors the power supply voltage.
7 citations
01 Sep 1996
TL;DR: A wearable digital hearing aid prototype is described which is based on a fixed-point digital signal processor and enables the testing of even highly sophisticated algorithms, with a changing interval of the accumulator pack of 10 hours.
Abstract: The benefit of hearing aid algorithms in everyday life can hardly be estimated from results obtained in the laboratory. Extensive field tests with many hearing impaired subjects are necessary to evaluate these processing schemes. A wearable digital hearing aid prototype is described which was developed specifically for that purpose. It is based on a fixed-point digital signal processor. This unit enables the testing of even highly sophisticated algorithms, with a changing interval of the accumulator pack of 10 hours. As application examples, a very flexible three channel dynamic compression algorithm and a binaural processing scheme for enhancing speech signals in noisy and reverberant environments are described. Application of 20 units in 3 European clinics has been started recently.
5 citations
31 Oct 1996
TL;DR: An indirect way to evaluate and predict the performance of a hearing aid system without the help of such a subject-based test is proposed.
Abstract: With the advent of high speed digital signal processing chips, many digital techniques have been introduced to hearing aids. As new techniques are developed a subject-based test is needed to verify the performance of each new technique, which requires much time and cost. Here, the authors propose an indirect way to evaluate and predict the performance of a hearing aid system without the help of such a subject-based test. The system is developed based on a model constructed from the auditory test results of sensorineural hearing impaired persons. To verify the proposed system, a processed signal was heard by normal persons and their responses were compared with those of a real impaired person. The results showed only a slight difference between them. In addition, 3 kinds of currently available digital hearing aid algorithm were applied to the system and evaluated.
5 citations
03 Nov 1996
TL;DR: This paper presents three quantitative measures of evaluating the processed signal, using the adaptive noise reduction option, and correlates these measures with qualitative feedback obtained from human subjects.
Abstract: This paper addresses perceptual measures, both quantitative and qualitative (subjective) that are indicative of the effectiveness of the speech processing performed by a digital hearing aid. The system (based on Texas Instruments TMS320C3X digital signal processing (DSP) chip) can implement spectral shaping, noise reduction (speech enhancement), multichannel compression and multichannel interaural delay. This paper presents three quantitative measures of evaluating the processed signal, using the adaptive noise reduction option, and correlates these measures with qualitative feedback obtained from human subjects. The three quantitative measures discussed are signal to noise ratio (SNR) improvement, relative signal power using the power density spectrum, and spectral distance measured by root mean square (RMS) logarithm spectral distortion. For the subjective measure, an experiment was designed using a test data set consisting of eight sentences.
3 citations
Patent•
26 Mar 1996TL;DR: In this article, the first-in-first-out principle was used to store the acoustic input signals in the amplifier circuit, and the stored signals were only available via the storage element.
Abstract: The amplifier circuit comprises circuitry with a time window. The circuitry includes a storage element (6) which digitally stores temporarily the acoustic input signals which are received within the time window. The storage of the acoustic signals is performed according to the first-in first-out principle. A register is used as the storage element. When the stored signals are read, signals are only available via the storage element.
2 citations
TL;DR: An algorithm for a wearable prototype digital hearing aid processor that enables the hearing aid wearer to better utilize their binaural directional hearing ability is described.
Abstract: An algorithm for a wearable prototype digital hearing aid processor will be described. The algorithm enables the hearing aid wearer to better utilize their binaural directional hearing ability. Fitting of the algorithm is accomplished in two steps: Hearing aid equalization (HAE) and hearing loss compensation (HLC). HAE equalizes the amplitude and phase insertion effects of the aids and maintains the binaural cues with the aids in place. The HAE digital filters for each ear are obtained from in situ probe tube measurements of aided and unaided test signals. HLC for each ear is also achieved with digital filters and associated gain. The target response for each HLC filter is determined from auditory thresholds and sound field reference signals, and is based on an adaptation of articulation theory. The response of the HLC filter can be modified to prevent acoustic feedback. The HAE and HLC filters are combined to produce a single digital filter. A description of the processor, fitting algorithm, and the hard...
1 citations
04 Nov 1996
TL;DR: This design project has a lot of future potential and follow on work ahead, and would probably involve designing and building an ASIC that would be specifically tailored for usage in a hearing aid.
Abstract: This design project has a lot of future potential and follow on work ahead. As improvements are made in the miniaturization of circuitry, the concept of a programmable digitized hearing aid grows more feasible. The one that was built and tested as a part of this project had several shortcomings that were related to using non-specialized components. To be useful to the consumer, it needs to be repackaged into a smaller, more efficient case. The power consumption needs to be minimized over the current power requirements. This would probably involve designing and building an ASIC that would be specifically tailored for usage in a hearing aid. A user friendly PC based interface program needs to be written to allow easier updates to the hearing profile tables that are stored in non-violative memory.