H.-Y. ChienT.-M. ShenT.-Y. HuangRUEY-BEEI WU2018-09-102018-09-102009-0700189480http://scholars.lib.ntu.edu.tw/handle/123456789/351842https://www.scopus.com/inward/record.uri?eid=2-s2.0-68349123659&doi=10.1109%2fTMTT.2009.2022591&partnerID=40&md5=c7b8507cae00df0148f96f76acd2aed3This paper proposes miniaturized bandpass filters with double-folded substrate integrated waveguide (SIW) resonators using multilayer low-temperature co-fired ceramic (LTCC) technology. Formed by inserting a metal plate with two orthogonal slots into the cavity, the double-folded SIW resonator is used for the circuit size reduction with its footprint about a quarter of the conventional TE101 mode. With LTCC technology, there is more flexibility to organize the cavities of filters because of the 3-D arrangement. The vertically stacked cavities are coupled by "L"- or "U"-shaped slots, and if arranged horizontally, by an inductive window on the common sidewall or a suspended stripline between the cavities. Through experimental measurements and simulations at both the Ka- V -bands, it has been demonstrated that the proposed filter has compact sizes and good frequency responses. The area of the fully stacked Chebyshev filter has 88% size reduction in comparison with a three-pole planar waveguide filter, while the vertically stacked quasi-elliptic filter has 74% size reduction in comparison with a four-pole planar waveguide filter. © 2006 IEEE.Bandpass filter; Cavity; Coupling coefficient; Folded waveguide resonator; Low-temperature co-fired ceramic (LTCC); Miniaturized filterCavity; Coupling coefficient; Folded waveguide resonator; Low-temperature co-fired ceramic (LTCC); Miniaturized filter; Ceramic materials; Circular waveguides; Frequency bands; Frequency response; IIR filters; Microwave circuits; Planar waveguides; Plate metal; Poles; Resonators; Size determination; Three dimensional; Wave filters; Windows; Bandpass filtersjournal article10.1109/TMTT.2009.20225912-s2.0-68349123659WOS:000268034500019