摘要

This paper presents an X-band three-channel thermoelectric radio frequency microelectromechanical systems (RF MEMS) power sensor with three inputs and one output, in order to measure the power with up to three RF signals. This power sensor is based on the principle of power-heat-voltage conversion and accomplished with the GaAs monolithic microwave integrated circuit (MMIC) technology. The three inputs are used to transmit RF signals over coplanar waveguide (CPW) lines and the one output collects the thermovoltage. To show good electromagnetic and thermal isolations, signal crosstalks for the three-input and one-output power sensor are quantified by the S-parameters simulation and the power handling measurement, respectively. In addition, the measured power sensor has resulted in three input reflection coefficients of less than -21.5 dB for frequencies up to 12 GHz. Experiments demonstrate the sensor has the good linearity of the power with respect to the thermovoltage at X-band, with sensitivities of about 53.1 mu V mW(-1), 56.3 mu V mW(-1), 58.9 mu V mW(-1) for the three inputs at 12 GHz, respectively.