An Electronically Tunable High-Power Impedance Tuner With Integrated Closed-Loop Control

In this letter, a novel electronically tunable, high-power and highly linear impedance tuner with integrated closed-loop control is experimentally demonstrated. The structure of the proposed tuner is based on two individually controlled substrate-integrated cavities, implemented as evanescent-mode magnetically coupled resonators. A prototype tuner at 3.3 GHz is designed, fabricated, and successfully measured with up to 90-W input power. The reported experimental results show more than 90% coverage of Smith chart at the center frequency and about 37% frequency bandwidth for covering at least half of the Smith chart. Also, the measured IIP3 and power loss are +64.3 dBm and 0.77 dB, respectively. The proposed tuner is suitable for high-power applications including radars and base stations.