Multiplex signal processing apparatus
US5061999A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 9, 1988 |
| Grant date | Oct 29, 1991 |
| Priority date | — |
| Expiry date | Nov 9, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N11/30
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A signal of the same frequency band as an ordinary NTSC signal of the video signals is transmitted with the conventional frequency band but the other frequency components are frequency-converted to a frequency higher than the sound subcarrier as the multiplex signal. The ordinary video signal, sound subcarrier and multiplex signal are frequency-multiplexed and the main carrier is transmitted by angle modulation as the modulation signal. In this case, as the multiplex signal, a signal other than the ordinary signal may directly be frequency-multiplexed and the signal may be multiplexed. Using amplitude or angle modulation to improve the demodulation accuracy or S/N through the angle modulation. The ordinary signal is regenerated like in the conventional system, without influence on the conventional receiver. In addition, since the ordinary video signal and the multiplex signal are separated in the frequency band, these may be used as the independent new transmission bands. Therefore, information other than the video signal can also be transmitted.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.