Microwave power amplifier

A power amplifier comprising of;

• a drive amplifier composed of one or two or more transistors to amplify an input signal;
• an intermediate stage amplifier composed of two transistors;
• a GCPW, a waveguide, and a first spatial combiner unit which are sequentially connected between the drive amplifier and the intermediate stage amplifier to divide a signal output from the drive amplifier and provide the divided signal to the transistors of the intermediate stage amplifier;
• a final stage amplifier composed of 4 transistors;
• a second spatial combiner unit, a waveguide divider, and a third spatial combiner unit which are sequentially connected between the intermediate stage amplifier and the final stage amplifier to divide signals output from the intermediate stage amplifier and provide the divided signals to the transistors of the final stage amplifier;
• and
• a fourth spatial combiner unit and a waveguide combiner which are sequentially connected to the output terminal of the final stage amplifier to combine signals output from the transistors of the final stage amplifier and finally output the combined signals.