To secure satisfactory noise index characteristics, to suppress the occurrence of distortion caused by excessive input in a mixer or gain variable amplifier and to stably operate a feedback loop at all the time.

A control circuit performs control so that while a received RF signal is a small level, the gain of a low noise amplifier circuit is maximized and while the received RF signal is a maximum level, the gain of the low noise amplifier circuit is minimized. Therefore, while the received RF signal is the small level, satisfactory noise index characteristics are secured and while the received RF signal is the maximum level, the excessive input is not inputted to the mixer or gain variable amplifier on the following stage. Thus, the occurrence of distortion caused by the excessive input is suppressed by preventing the mixer or gain variable amplifier from being saturated. Further, the low noise amplifier circuit, the gains of the mixer and the gain variable amplifier are controlled in the almost similar ratio, and the transient response of the feedback loop is reduced so that stable operation can be provided.