A digital video receiver front end circuit and automatic gain control method

Automatic gain control method for a digital video receiver front end circuit, comprising the following steps: firstly, receiving a radio frequency signal and converting the RF signal to an intermediate frequency signal. Then, according to a gain amplifying the intermediate frequency signal. Subsequently, the amplified IF signal to a demodulated baseband signal and a baseband signal is a coded serial signal is transmitted. Next, using at least one variable resistor controlling a DC component of the pulse width modulated signal to adjust the gain, the pulse width modulation signal related to the set gain. Thereafter, the power level of one or more radio frequency signals, each group may read bit error rate and the variable gain setting resistor, and based on the bit error rate to select the best gain and the variable resistor set up.