A Frequency-Compensation-Type Microwave Power Sensor Fabricated by GaAs MMIC Process

In this letter, a novel microwave power sensor is proposed to accomplish frequency compensation for 1-20-GHz application. Compared with traditional power sensor, this design has two extra power compensation ports in order to adjust the output voltage. This device is designed and fabricated with GaAs MMIC process. The measured return loss of three ports is less than -26 dB over 1-20 GHz. The output voltage increases with the incident power and the sensitivity is close to 0.115, 0.111, and 0.106 mV/mW at 1, 10, and 20 GHz, respectively. Frequency compensation is performed and the output voltage is compensated to that of 10 GHz. Clearly, when the incident power is fixed, the curve after compensation is flat and the voltage does not change with the frequency of the signal anymore.