Tunable SIW Band Pass Filters

Abstract

This paper presents a novel technique for tuning center frequency of substrate integrated waveguide (SIW) band pass filter (BPF), by loading simple dielectric rods of different dielectric materials on resonant cavities and coupling apertures. Tunability in center frequency of SIW BPF is first estimated with the help of full-wave 3D EM simulator and then verified experimentally. Tunability is achieved with variation in position, dimension and permittivity of dielectric rods. This initial investigation demonstrates a wide tuning capability of the proposed technique with an insertion loss less than 2dB and return loss greater than 10dB in X-band.