Protection of energy information in sub-band coding
US4805193A · kind A · utility
21Cited by
10References
23Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 4, 1987 |
| Grant date | Feb 14, 1989 |
| Priority date | — |
| Expiry date | Jun 4, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L19/005
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A digital communication system for transmission and reception of speech signals and utilizing sampling, filtering and sub-band coding techniques for reduction of the bit rate. The energy levels of each sub-band are determined with respect to the band having the maximum energy level. The energy level information is encoded and divided into protected and unprotected bits. Only the protected bits are used for the determination of the bit allocation of the sample information, but both protected and unprotected bits are utilized in reconstituting the original levels of the bands.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.