What is an automatic gain control?
It is a closed loop feedback regulating in an amplifier or chain of amplifiers, the purpose of which is to maintain a suitable signal amplitude at its output, despite variation of the signal amplitude at the output.
1. Explain the purpose of automatic gain control in radio receiver
The AGC circuit keeps the receiver’s output level from fluctuating too much by detecting the overall strength of the signal and automatically adjusting the gain of the receiver to maintain the output level within an acceptable range. It is used in most radio receiver to eaualize the average volume (loudness) of different radio stations due to differences in received signal strength.
- Explain the purpose of carrier wave frequency
The purpose of the carrier is usually either to transmit the information through space as an electromagnetic wave ( as in radio communication) or to allow several carriers at different frequency to share a common physical transmission medium by frequency division multiplexing ( as in a cable television system)
