Mapping of digital data symbols onto one or more formant frequencies for transmission over a coded voice channel
US6208959A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 15, 1997 |
| Grant date | Mar 27, 2001 |
| Priority date | — |
| Expiry date | Dec 15, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L19/00
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A digital input symbol is transmitted to a receiver by determining one or more formant frequencies that correspond to the digital input symbol. In one embodiment, a pre-programmed addressable memory is used to map the set of possible digital input symbols onto a set of corresponding speech units, each comprising a superposition of one or more formant frequencies. A signal is then generated having the speech units. The signal is supplied for transmission over a voice channel. This may include supplying the signal to a voice coder prior to transmission. In another aspect of the invention, a forward error correction code (FEC) is determined for the digital input symbol, and the one or more speech units are modified as a function of the forward error correction code. In this way, the FEC may also be transmitted with the encoded input symbol. The modification may affect any of a number of attributes of the speech units, including a volume attribute and a pitch attribute.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.