A voltage source model on thermoelectric power sensor based on MEMS technology

摘要

In order to achieve monolithic integration of thermoelectric power sensor and its amplification system and improve the measurement accuracy of microwave power, a voltage source model is researched in this paper. And the thermoelectric power sensor is designed and fabricated using MEMS technology and GaAs MMIC process. It is measured in the X-band (8–12 GHz) with the input power in 100 mW range. When the input microwave power is at 10, 50 and 100 mW, respectively, the frequency dependent coefficient k₁ is −0.073, −0.39 and −0.82 mV/GHz, respectively. The sensitivity coefficient k₂ is 0.311, 0.303, 0.293, 0.284 and 0.279 mV/mW at 8, 9, 10, 11 and 12 GHz, respectively, and has an excellent linearity. Based on the voltage source model, the feedback coefficient of its amplification system is set to 0.0078 × P_in to compensate the loss power caused by frequency dependent characteristic. In addition to miniaturization and low cost, an advantage using this model is significantly improved measurement accuracy.