Patent ID: 6873208

Claim:
A high-frequency amplifying device for amplifying a high-frequency signal with a plurality of stages of amplifying elements, comprising: a high-frequency amplifying unit including a plurality of amplifying elements configured to amplify an input high-frequency signal; a measuring circuit configured to measure an amplitude of the input high-frequency signal; and a plurality of bias control circuits configured to respectively independently and continuously control biases applied to respective amplifying elements according to a value of amplitude measured by said measuring circuit, wherein the plurality of bias control circuits includes at least a first bias control unit and a second bias control unit, the first bias control unit including a current subtracting unit configured to output a difference current corresponding to a difference between a first input current and a first predetermined current, and the second bias control unit including a current adding unit configured to output a sum current corresponding to a sum of a second input current and a second predetermined current.