Comfort noise generation for digital communication systems
US5630016A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 7, 1996 |
| Grant date | May 13, 1997 |
| Priority date | — |
| Expiry date | Mar 7, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L19/012
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A digital discontinuous cellular communication system has a transmitter that transmits two frames of data following detection of voice inactivity. A receiver includes a comfort noise generator that uses the two frames of data to output noise to the speaker during period of voice inactivity. The comfort noise generator includes synthesis codebook with samples scaled by actual background noise and excitation codebook with samples filtered and scaled by the background noise that are combined to produce comfort noise having attributes and loudness level of the received background noise prior to interruption of transmission. The scaled signals are weighted to vary the loudness level and spectral attributes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.