A Novel Miniaturization Doubled Folded Quarter Mode Substrate Integrate Waveguide Tunable Filter Design in LTCC

A novel doubled folded quarter mode substrate integrate waveguide (DFQMSIW) resonator based on low temperature co-fired ceramic(L TCC) is proposed, and a plane cascade connected DFQMSIW tunable filter is design based on the resonator. The plane cascade double-order DFQMSIW tunable filter realizes the center frequency linearity, which works at 1.6GHz with the adjustable range of 51.8% and the insertion loss is 1.2dB, return loss is less than -15dB. The coplanar cavity coupling structure achieves the bandwidth switchable.