Transmission system with suppressed carrier signal amplitude modulation preserving the polarity of the transmitted signal, and corresponding transmitter and receiver
US5077542A · kind A · utility
Assignees
Inventor
Key dates
| Filing date | Dec 7, 1990 |
| Grant date | Dec 31, 1991 |
| Priority date | — |
| Expiry date | Dec 7, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/40
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A system of transmission with amplitude modulation for the transmission of signals of all types, analog and/or digital, requiring high performance characteristics with respect to the noise induced by the transmission channel, comprising, at transmission, means for the suppressed carrier amplitude modulation of a useful signal and means for the amplitude modulation, in phase quadrature with said modulated useful signal, of a service signal, making it possible, at reception, to remove the ambiguity on the polarity of the demodulated useful signal. Thus it enables the transmission of signals in suppressed carrier modulation mode, hence with a good signal-to-noise ratio, without losing the polarity of the signal. The transmitters and receivers according to the invention also enable the transmission and reception of the signals modulated in SCAM, VSBAM or VSBSCAM modes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.