Design of Ultra-Wideband Substrate Integrated Waveguide (SIW) Filters in Zigzag Topology

In this letter we propose a modified substrate integrated waveguide (SIW) zigzag filter topology, which allows the flexible introduction of extra cross-couplings between non adjacent resonators. This novel topology permits to control the location of the transmission zeros, thus improving the resulting filter selectivity. Therefore, it has been used to design filters in compliance with the restrictive ultra-wideband European mask. In order to validate the new proposed topology, two filter prototypes have been designed, manufactured and measured, showing very good agreement with simulation data.