Compandor noise reduction circuit
US4600902A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 1, 1983 |
| Grant date | Jul 15, 1986 |
| Priority date | — |
| Expiry date | Jul 1, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03G9/025
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
There is disclosed an analog signal processing circuit (compandor) and a method for overcoming noise in a transmission medium by means of a composite compressor and composite expander. The composite compressor splits the frequency spectrum of the analog signal into two or more frequency components, compresses all of the frequency components in parallel with the same 3:1 integer compression ratio, combines the compressed frequency components to produce a compressed analog signal, and transmits the compressed analog signal on the transmission medium. The composite expander reconstructs the original analog signal by means of feedback loop which extracts one of the compressed frequency components from the compressed analog signal, expands that extracted compressed frequency component to produce an expanded frequency component, derives the other expanded frequency components from the first expanded frequency component, compresses the derived expanded frequency components which are used to extract the first compressed frequency component, and a combining circuit which combines the expanded frequency components to reconstruct the original analog signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.