| 摘要 |
PURPOSE:To realize a wide band via the feedback circuit and by using the dual gate FET to the microwave amplifier. CONSTITUTION:The microwave signal applied to input terminal IN is applied to 1st gate G1 via input/output matching circuit M1, and the amplification output is delivered to output terminal OUT via input/output matching circuit M2. Part of the microwave amplification output is drawn out by coupler 2 (using the region where the coupling amount changes monotonously) and then converted into the direct current via diode 3 to be applied to operational amplifier 5 to which the reference voltae is set up. And the output is applied to 2nd gate G2 of FET1. The output of coupler 2 decreases as the frequency increases, and the negative voltage applied to gate G2 decreases in terms of the absolute value as the frequency increases. As a result, the gain can be increased for the higher frequency band. |
