| 摘要 |
PROBLEM TO BE SOLVED: To provide an automatic gain control circuit, its method, and demodulator, which can conduct fast and accurate level capture and can prevent errors and system disruption. SOLUTION: An automatic gain amplifier 211 is provided: when a trigger signal for burst detection start is received, a gain control signal is outputted to the amplifier 211, and when a first burst synchronism detection signal is received by a burst detection unit, a second gain is calculated based on a received signal power detected by a received signal power monitor 202 and a gain control signal is outputted to the amplifier 211 so as to amplify at the second gain, and upon receipt of a digital reception signal amplified at the second gain, integral is calculated to determine the received signal power, and when a second burst synchronism detection signal is received by the burst detection unit, a third gain is calculated based on the determined received signal power and a gain control signal is outputted to the amplifier 211 so as to amplify at the third gain. |
