The New Filters Based Research SIW Structure

In recent years, with an ever-growing advancement and deployment of new wireless communications in millimeter-wave band, the substrate integrated waveguide (SIW) structure has stimulated an unprecedented enthusiasm in both academia and industry due to its unique features and diverse advantages, just name a few:high quality factor, high power-handling capability, low profile, easy fabrication, good integration, etc. In this dissertation, the author has proposed several novel SIW-based filters with different operating frequencies and multiple functions for potentially commercial applications.After design procedure of a SIW filter is introduced, several works on SIW filters adopting low temperature co-fired ceramic (LTCC) technology are carried out:At first, a60GHz single-band bandpass filter with compact circuit size and high filtering selectively is proposed; Then, based on the aforementioned structure, a modified topology is developed to realize the dual-band response; In final, a45GHz3-D integrated bandpass filter with four controllable transmission zeros has been demonstrated by virtue of extracted-pole and cross-coupling mechanisms for simultaneous design-freedom enhancement and topology-sensitivity reduction.In addition, research on the design of differential-mode (DM) bandpass filters is also carried out based on the SIW technology. By properly arranging the topologies of cavities, a balanced section is constructed to achieve an attractive capacity in simultaneously realizing the desired DM transmission and expected common-mode (CM) suppression in a certain band. In design, the specified DM frequency response is achieved with an equivalent two-port circuit model. A single-band and a dual-band prototypes operating at Ku-and X-band respectively are designed and fabricated on a single-layer substrate, and the measured results agree well with the predicted counterparts.