Speech recognition apparatus
US5390280A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 10, 1992 |
| Grant date | Feb 14, 1995 |
| Priority date | — |
| Expiry date | Nov 10, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L15/20
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A noise signal supplied from a microphone by way of an analog to digital converter is Fourier converted to calculate a power spectrum of the noise signal by a Fourier converting section. A system controller compares an average value of the power spectrum of the signal being outputted from the microphone at present and an average value of the power spectrum of a noise signal stored in a noise memory at present with each other. When the system controller determines that the difference between the average value of the power spectrum of the signal being outputted from the microphone at present and the average value of the power spectrum of the noise signal stored in the noise memory at present is higher than a predetermined reference value, it outputs a controlling signal to a sound storing and reading out section to store the signal being outputted from the microphone at present into the noise memory. Consequently, the signal being outputted from the microphone at present is stored into the noise memory in place of the noise signal stored in the noise signal at present.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.