Design and Modeling of a Miniaturized Substrate Integrated Waveguide Using Embedded SRRs

F Farzami,K Forooraghi,M Norooziarab

doi:10.1109/lawp.2011.2161860

F Farzami, K Forooraghi + Show 1 more

Open Access

https://doi.org/10.1109/lawp.2011.2161860

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Abstract

A substrate integrated waveguide (SIW) loaded by embedded split-ring resonators (SRRs) with transversal negative effective permeability is proposed. It is shown that the structure can support propagation of backward waves below cutoff frequency. Therefore, the width of the SIW structure can be considered less than half a wavelength at the cutoff frequency, which means that the SIW structure is miniaturized. In this letter, design and modeling of a miniaturized SIW structure is proposed. An experimental SIW loaded with double embedded SRRs in 4.75-GHz frequency band has been designed, fabricated, and tested. The measured and simulated results show a passband for backward waves below the cutoff frequency. It is also shown that the phase at a certain frequency in the backward passband increases as the physical length of the loaded SIW is increased (opposite to forward wave propagation), which proves that backward waves propagate below the cutoff frequency.

Highlights

A substrate integrated waveguide (SIW) is similar to a rectangular waveguide filled with a dielectric, except for the narrow walls which are replaced by two rows of metal cylinders, Fig
If the distances between the vias are small enough compared to the wavelength, the propagation characteristics of the SIW can be considered as a typical metallic rectangular waveguide [1]
Split ring resonators (SRRs) which are a kind of metamaterials have been widely used in many microwave and millimeter wave components; because of their natural resonant property and that they can show negative permeability

Summary

INTRODUCTION

A substrate integrated waveguide (SIW) is similar to a rectangular waveguide filled with a dielectric, except for the narrow walls which are replaced by two rows of metal cylinders (vias), Fig.. The most important advantage of SIWs relative to rectangular waveguides is that they can be integrated with planar structures. Split ring resonators (SRRs) which are a kind of metamaterials have been widely used in many microwave and millimeter wave components; because of their natural resonant property and that they can show negative permeability. It is shown that an SIW can be miniaturized when it is loaded by these embedded SRRs. It is shown that the cutoff frequency of the waveguide structure can be arbitrarily tuned if the SRRs are designed properly. The structure is loaded by double embedded SRRs to provide a passband for backward waves in 4.75 GHz. the structure is fabricated and measured.

WAVEGUIDE STRUCTURE

The SRR structure

THE EFFECT OF LOADING SIW WITH SRRS

CONCLUSION