Multiple QAM digital television signal decoder
US5386239A · kind A · utility
63Cited by
9References
14Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 14, 1994 |
| Grant date | Jan 31, 1995 |
| Priority date | — |
| Expiry date | Mar 14, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/2647
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a video signal processing system, a single adaptive passband equalizer is used to process a composite Quadrature Amplitude Modulated (QAM) signal encoded with high priority (HP) and standard priority (SP) components. The equalizer output is phase corrected by a de-rotator, and filtered to separate the HP and SP components. Error signals respectively representing HP and SP phase errors are developed. One of the error signals controls the operation of the de-rotator. Both error signals are used to generate updated coefficients for the adaptive equalizer. Afterwards the HP and SP components are decoded and combined.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.