Digital carrier combining apparatus in a multiple QAM digital television signal receiver
US5313279A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 16, 1992 |
| Grant date | May 17, 1994 |
| Priority date | — |
| Expiry date | Dec 16, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/30
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a high definition television signal encoder, high priority and standard priority digital data are each separated into quadrature I and Q components, spectrally shaped by digital filtering, and time division multiplexed to produce respective quadrature amplitude modulated signals of the 32-QAM type. The high priority QAM signal and the standard priority QAM signal exhibit different bandwidths and carrier frequencies. The high priority and standard priority QAM signals are combined in digital form to produce a prioritized dual 32-QAM digital signal before being conveyed to a single analog-to-digital converter and analog RF transmission networks.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.