PURPOSE: To improve the efficiency by allowing a switching regulator only to apply on/off control of a drain of an FET being a component of a power amplifier so as to reduce the power loss of the power amplifier.
CONSTITUTION: An input 1 is connected to a power distributer 2 and each of the distributed power is fed to microwave amplifiers A1∼AN comprising a corresponding FET. Each amplified power is combined by a power combiner 3 and then outputted. An output of switching regulators 41∼4N receiving an AC voltage and generating a drain voltage is connected to the FETs of the amplifiers A1∼AN. The oscillator of the regulators 41∼4N is controlled by a control circuit 5. The power loss is reduced by controlling the FETs constituting the amplifiers A1∼AN not by any transistor or diode but by the regulators 41∼4N in this way.
KANEKO YOSHIAKI
SAITO TOSHIYUKI
