A GaAs MMIC-based X-band Dual Channel Microwave Phase Detector based on MEMS Microwave Power Sensors

Abstract

By sensing the output powers of two channels with MEMS microwave power sensors, a wideband 8-12GHz dual channel microwave phase detector is presented. In order to detect phase difference between reference signal and testing signal in entire 0-360° at X-band, artificial 45° phase lead and 45° phase lag are introduced in two channels, additionally. The proposed phase detector is composed of power dividers, power combiners, 45° (at 10GHz) coplanar waveguide (CPW) transmission delay lines, MEMS capacitive power sensors and thermoelectric power sensors. The two CPW transmission lines result in 45° phase lead and 45° phase lag at 10GHz, and the two different kinds of power sensors are used to detect the combined powers. The fabrication of the phase detector is compatible with GaAs Microwave Monolithic Integrated Circuit (MMIC) technology. The phase detection measurement is accomplished at 10GHz with 0-180° phase shift between testing signals generated by a tunable analog phase shifter. Phase detection results in two channels show that the normalization of the measured results fit the calculated results well, though the results of phase lead have a little of deviation.