Automatic gain control system
US4630117A · kind A · utility
14Cited by
5References
6Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | May 30, 1985 |
| Grant date | Dec 16, 1986 |
| Priority date | — |
| Expiry date | May 30, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/52
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An automatic gain control system which measures the noise content of a received video signal and adjusts the gain of a radio frequency amplifier and a tuner to compensate for variations in noise levels. The apparatus uses a high frequency filter to strip the video information portion of a composite video signal to obtain only the noise component. The noise component is scaled and used in an automatic gain control feedback loop to control the gain of a radio frequency amplifier and a tuner. The system includes a standard AGC loop to regulate tuner gain for large amplitude signals to prevent overload.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.