Development research of thermocouple-based microwave power sensors using AC/DC substitution method

Abstract In this work, a thermocouple-based microwave power sensor using AC/DC substitution method is developed. The reason that the output voltage is different under different microwave frequency is explained. An improved package solution of the thermocouple-based microwave power sensor is designed at X-band (8–12 GHz). The fabrication of this thermocouple-based microwave power sensor is divided into a front side and a back side processing using GaAs MMIC process and MEMS technology. The measurement results show that the output voltage of the microwave power sensor decreases with increasing microwave frequency, and the COB (Chip on Board) technology brings an economic package solution for the thermocouple-based microwave power sensor. The microwave power sensor after package can be applied into the radar system and other microwave system.

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