Microfluidic-Based Ultra-Wide Tuning Technique for TM010 Mode Dielectric Resonators and Filters

This paper introduces a new technique of designing widely frequency tunable TM010 mode dielectric-loaded waveguide resonators and filters. The proposed tuning method is based on using liquid metals to tune the resonant frequency by altering the liquid level inside the resonator hollow-channel. A single-pole bandpass filter is designed, fabricated, and measured for proof-of-concept purposes. The realized filter demonstrated wide frequency tuning from 2.33 GHz to 0.67 GHz maintaining low insertion loss < 1 dB allover the tuning window. The presented results exhibit the great potential of the proposed technique in high-performance widely-tunable next-generation RF systems.