Self-adjusting dual mode automatic gain control circuit
US4371842A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 24, 1980 |
| Grant date | Feb 1, 1983 |
| Priority date | — |
| Expiry date | Oct 24, 2000 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03G3/20
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An automatic gain control circuit comprising a gain-controlled amplifier for receiving a variable amplitude, pulse-type input signal to produce a substantially constant amplitude, pulse-type output signal which is applied to a feedback circuit for comparison with a predetermined reference voltage to generate a control voltage to set the gain of the amplifier. A voltage limiter included in the feedback circuit clips the pulse peaks of the output signal whenever the peaks exceed a predetermined amplitude so that the gain of the amplifier is reduced in a prescribed manner to preclude output signal dropout. A peak detector and a filter included in the feedback circuit are capable of operating in fast and slow modes. When operating in the fast mode, the peak detector responds essentially to each pulse peak of the output signal and the filter has a wide bandwidth so that the automatic gain control circuit operates with a prescribed fast time response. When operating in the slow mode, the peak detector operates to increase the gain of the amplifier slowly in order to limit output signal overshoot and preclude output signal dropout if the input signal reappears after an absence for some pe…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.