A novel gradient thermoelectric microwave power sensors based on GaAs MMIC technology

A novel gradient thermoelectric microwave power sensor is designed to improve the performance in this work. The thermocouples are designed with different lengths based on the thermal distribution of resistance. It is fabricated using GaAs MMIC technology, and it can be integrated with other planar circuit structures. The thermal distribution of the gradient thermoelectric microwave power sensor is simulated by ANSYS finite element software. The performances of the gradient thermoelectric microwave power sensors are measured. The result shows that return loss is better than − 25 dB at 8–12 GHz. It reveals that this structure has a low reflection loss and a good matching characteristic. The sensitivity is 9.6 mV/W@8 GHz, 8.7 mV/W@10 GHz and 7.8 mV/W@12 GHz, respectively, and an excellent linear relationship of the output voltage with the input microwave power is obtained. Therefore, this optimized design of thermocouples has certain reference value for thermoelectric microwave power sensors.