Speech coding hearing aid system utilizing formant frequency transformation
US4051331A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 29, 1976 |
| Grant date | Sep 27, 1977 |
| Priority date | — |
| Expiry date | Mar 29, 1996 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R2225/43
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A hearing aid system and method includes apparatus for receiving a spoken speech signal, apparatus coupled to the receiving apparatus for determining at successive intervals in the speech signal the frequency and amplitude of the largest formants, apparatus for determining at successive intervals the fundamental frequency of the speech signal, and apparatus for determining at successive intervals whether or not the speed signal is voiced or unvoiced. Each successively determined formant frequency is divided by a fixed value, greater than 1, and added thereto is another fixed value, to obtain what are called transposed formant frequencies. The fundamental frequency is also divided by a fixed value, greater than 1, to obtain a transposed fundamental frequency. At the successive intervals, sine waves having frequencies corresponding to the transposed formant frequencies and the transposed fundamental frequency are generated, and these sine waves are combined to obtain an output signal which is applied to a transducer for producing an auditory signal. The amplitudes of the sine waves are functions of the amplitudes of corresponding formants. If it is determined that the speech signal i…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.