Guided-wave and leakage characteristics of substrate integrated waveguide

TLDR

SIW enables fabrication of complete planar circuits, transitions, and rectangular waveguides on standard PCBs. The study investigates guided‑wave and mode characteristics of an SIW periodic structure and introduces a numerical multimode calibration method. The authors employ a full‑wave finite‑element multimode calibration procedure, simulate two SIW lengths under multimode excitation, and perform experiments to validate the method. The technique accurately extracts complex propagation constants for each SIW mode, reveals electromagnetic band‑stop behavior in periodic structures, and yields simple design rules.

Abstract

The substrate integrated waveguide (SIW) technique makes it possible that a complete circuit including planar circuitry, transitions, and rectangular waveguides are fabricated in planar form using a standard printed circuit board or other planar processing techniques. In this paper, guided wave and modes characteristics of such an SIW periodic structure are studied in detail for the first time. A numerical multimode calibration procedure is proposed and developed with a commercial software package on the basis of a full-wave finite-element method for the accurate extraction of complex propagation constants of the SIW structure. Two different lengths of the SIW are numerically simulated under multimode excitation. By means of our proposed technique, the complex propagation constant of each SIW mode can accurately be extracted and the electromagnetic bandstop phenomena of periodic structures are also investigated. Experiments are made to validate our proposed technique. Simple design rules are provided and discussed.