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This paper builds a complete analytical model for self-assembling microwave power sensor with thermopile and curled cantilever beam. The power sensor consists of a thermoelectric power sensor for low power detection from 0.1 mW to 100 mW and a capacitive power sensor for high power detection from 100 mW to 800 mW. The curled cantilever beam is designed to improve the dynamic range and microwave performance of the power sensor. The analytical model includes an electromagnetic model, a static mechanical model, and a stationary heat transfer model. The electromagnetic model takes the S-parameter of indirect-heating thermoelectric power sensor into consideration. The static mechanical model considers the fringing fields between the curled cantilever beam and the measuring electrode as well as the initial curling induced by the stress gradient. The experimental results show a good agreement with the theory and validate the effectiveness of the presented models. Furthermore, good performance of the power sensor has found. The measured return loss is lower than −25.5 dB at 8–12 GHz and the output of the power sensor has good linearity with the incident radio frequency power up to 600 mW. [ABSTRACT FROM AUTHOR]

This paper reports a high dynamic range power sensor based on GaAs process and MEMS technology. The proposed sensor consisted of the terminating-type sensor and the coupling-type sensor. The former measures low power while the latter is for high power detection. This device is designed and fabricated by GaAs MMIC process. In order to optimize microwave performance, impedance compensating technology by increasing the slot width of the CPW transmission line is developed. Related calculation and simulation are also presented in this paper. The microwave performance test reveals that the return loss is close to −28 dB@8 GHz, −27 dB@10 GHz and −26 dB@12 GHz, respectively. The microwave power response experiment is investigated from 1 mW to 150 mW. For the incident power less than 100 mW, the terminating-type sensor operates and the measured sensitivity is about 0.095 mV/mW@8 GHz, 0.088 mV/mW@10 GHz and 0.084 mV/mW@12 GHz, respectively. Related lumped equivalent circuit models of the loaded resistors are developed to explain the loss induced by the frequency of the signal. For the incident power with the improved dynamic range from 100 mW to 150 mW, the coupling-type sensor is adopted and the measured sensitivity is about 9.2 μV/mW@8 GHz, 8.6 μV/mW@8 GHz and 9.0 μV/mW@12 GHz, respectively. [ABSTRACT FROM AUTHOR]