Analysis of Narrow Slot Loading on a Half Guided Wavelength Folded Substrate Integrated Waveguide

Abstract

In this paper, effects due to variation in positioning, width and length of a narrow slot loaded on central metal septum of a half guided wavelength Folded Substrate Integrated Waveguide (FSIW) segment is presented. The study shows that the most significant effect is due to variation in slot length. It was observed that the slot loading can be used both for slow wave structure and filter depending on the length of the slot. The smaller lengths of the slot provide the slow wave effect, whereas the longer lengths result in filtering effect. Both the phenomena are explained with the help of field diagrams for different propagating modes and extracted equivalent circuit for the Slot Loaded Folded Substrate Integrated Waveguide (SFSIW) segment. This study will help in deciding the dimensions of the slot as per application. The measured scattering parameters of the fabricated structure are compared with the simulated results obtained from the HFSS and the circuit simulator in ADS and are in good agreement.