Substrate integrated waveguide filter with embedded mixed source–load coupling

Abstract

A compact substrate integrated waveguide (SIW) filter with an improved stopband using multilayer embedded mixed coupling (MC) is presented. By implementing MC into the input/output SIW, the filter not only exhibits good rejection for the upper stopband, owing to an additional controllable transmission zero, but also has a miniature size of 18 × 12 mm 2 by profiting from its low-temperature co-fired ceramic structure. An experimental second-order filter with three TZs has been designed and fabricated. The measured results show good agreement with the simulated ones.

Compact QMSIW bandpass filter using composite right/left‐handed transmission line in grounded coplanar waveguide

“…It is more preferable to design circuits and systems at microwave frequency due to its low profile, high‐quality factor (Q‐factor), and easily integration with other planar circuits. Usually, SIW filter size is too large in lower frequency bands when compared with its counterparts of microstrip line …”

Design of Compact Wideband Qmsiw Band-Pass Filter With Improved Stopband

“…Substrate integrated waveguide (SIW) is an artificial waveguide structure which has attracted much attention to design low-cost and highly integrated waveguide filters for its high quality and easy connection with other planar transmission lines [1][2][3][4][5][6]. However, for lower microwave frequencies application, SIW is still too large.…”

Second-Order Mixed Coupling Filter With One Controllable Transmission Zero Using Multilayer Substrate Integrated Waveguide

“…In [5,6], the implementation of the mixed electric and magnetic coupling SIW filters with TZs for high selectivity have been reported, in which an inductive window between two SIW resonators introduces the magnetic coupling, and an embedded short-ended strip is employed to create the electric coupling, however, this filter is relatively large not only because of its planar arranging structure, but also due to suffering from the structure complexity and lack of flexibility, and there will be radiation loss if it operated in millimeter-wave bands. The application of SIW technology makes the realization of filters with the multilayer structure and compact size possible in [7][8][9][10][11][12]. The coupling between the vertically stacked SIW resonators can be introduced by etching the apertures with different sizes, positions and number on the middle metal layer.…”

“…The mixed coupling is realized by embedding apertures on the inductive window between the horizontally oriented cascade SIW resonators of the single layer. Hence, the high selectivity for the multilayer SIW filters are achieved in [11,12]. However, the filter which directly introduces mixed coupling by etching appropriate aperture structures between two vertically stacked SIW resonators has rarely been reported.…”