Investigation of Symmetry Influence in Substrate Integrated Waveguide (SIW) Band-Pass Filters using Symmetric Inductive Posts

摘要

We present the investigation of symmetry influence in substrate integrated waveguide (SIW) band-pass filters using symmetrical posts for the suppression of TEi0 modes, with i = 2,4, . . .. This is of particular importance for SIW band-pass filters with a wide bandwidth. We show theoretical and experimental results for a particular filter with a bandwidth of more than 28% demonstrating an improvement in the suppression of spurious transmission by 19 dB.