EDTV recording apparatus
US4879606A · kind A · utility
26Cited by
12References
11Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 6, 1988 |
| Grant date | Nov 7, 1989 |
| Priority date | — |
| Expiry date | Jun 6, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N11/30
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Extended definition television (EDTV) signals including a compatible composite wideband signal and a separate helper or extended definition signal are combined, for example, for recording purposes, using frequency multiplexing techniques. The helper signal is applied to a modulator, which produces a suppressed carrier modulated signal, to frequency shift the helper signal to a spectral band above the frequency band occupied by the compatible composite wideband signal. The frequency shifted and wideband signal are then added to form the combined signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.