Publications Repository - Gdańsk University of Technology

This paper presents a design of a new type of in-line pseudo-elliptic filters implemented in substrate integrated waveguide(SIW) technology. To realize transmission zeros in in-line topology,frequency-dependent couplings were used. Such dispersive couplingswere implemented as shorted stubs. The design process startswith the generation of a suitable starting point. To this end, anapproximation of SIW as a rectangular waveguide is used and a fastelectromagnetic solver based on mode-matching technique is utilized(Wave Wizard). The next step is the optimization process of afilter in a full-wave 3D EM simulator Ansoft HFSS. The Optimizationroutine employs a cost function involving zeros and poles of the rational functions approximating scattering parameters. To increase the speed of convergence, a built-in derivative calculation feature was used and zeros and poles and their derivatives with respect to design parameters were extracted using the vector fitting algorithm. Experimental validation of the method is demonstrated by a third-order filter with asymmetric response and a fifth-order filter with two transmission zeros in addition to an asymmetric response. The experimental results show good agreement between the simulated and measured data.

Authors

• mgr inż. Andrzej Jędrzejewski link open in new tab ,
• mgr inż. Natalia Leszczynska link open in new tab ,
• dr inż. Łukasz Szydłowski link open in new tab ,
• prof. dr hab. inż. Michał Mrozowski link open in new tab