Characterization of the Propagation Properties of the Half-Mode Substrate Integrated Waveguide

Abstract

Abstract-The propagation properties of the half-mode substrate integrated waveguide (HMSIW) are studied theoretically and experimentally in this paper. Two equivalent models of the HMSIW are introduced. With the first model, equations are derived to approximate the field distribution inside and outside the HMSIW. Using the second model, an approximate closed-form expression is deduced for calculating the equivalent width of an HMSIW that takes into account the effect of the fringing fields. The obtained design formulas are validated by simulations and experiments. Furthermore, the attenuation characteristics of the HMSIW are studied using the multiline method in the frequency range of 20-60 GHz. A numerical investigation is carried out to distinguish between the contributions of the conductive, dielectric, and radiation losses. As a validation, the measured attenuation constant of a fabricated HMSIW prototype is presented and compared with that of a microstrip (MS) line and a substrate integrated waveguide (SIW). The SIW is designed with the same cutoff frequency and fabricated on the same substrate as the HMSIW. The experimental results show that the HMSIW can be less lossy than the MS line and the SIW at frequencies above 40 GHz.Index Terms-Half-mode substrate integrated waveguide (HMSIW), propagation properties.

A compact double folded quarter mode substrate integrated waveguide (DFQMSIW) filter

“…d and S are the via diameter and the spacing between adjacent vias, respectively. The dominant resonant mode in the proposed DFQMSIW structure is still the TE 101 mode, but Q property is smaller, and its resonant frequency is given by Equation (3) [14],…”

“…ÁW is observed owing to the varied feeding position and the magnetic walls are not ideal due to fringing fields [14]. A DFQMSIW cavity with 9 Â 9 mm 2 area is designed on Taconic RF35…”

Compact rectangular waveguide to HMSIW transition

“….) modes can propagate in the HMSIW and the dominant mode is the TE 0:5;0 mode [3]. The two probes tapered on opposite sides of the substrate tapered in an antisymmetric structure, which employ spline curve to improve impedance matching with the rectangular waveguide.…”

“…Half mode substrate integrated waveguide (HMSIW) is a type of miniaturized SIW, which keeps the advantages of SIW but the size is nearly half reduced [2,3]. Based on HMSIW technology, many kinds of microwave and millimeter-wave components are designed [4,5,6].…”

X-Band Circularly Polarized HMSIW U-Slot Antenna

“…Thus, the reduction of the SIW size is a very desirable task. The most feasible solution is to exploit a half-mode SIW (HMSIW) technology [8]. The HMSIW technology preserves all advantages of the SIW technology and its size is reduced nearly by a half with lower design and fabrication complexity.…”