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Updated: Jan 4, 2026
13:44
Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
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Ultrawide Bandwidth Electromagnetic Wave Absorbers Using a High-capacitive Folded Spiral Frequency Selective Surface
1Department of Advanced Materials Engineering, Chungbuk National University, Cheongju, 28644, Korea.
Scientific Reports
|November 13, 2019
Summary
A novel folded spiral conductor frequency selective surface (FSS) enables ultra-wide bandwidth absorption. This design achieves a broad absorption range with a compact, multilayer structure, demonstrating practical potential for advanced electromagnetic applications.
Area of Science:
- Electromagnetics
- Materials Science
Background:
- Frequency Selective Surfaces (FSS) are crucial for controlling electromagnetic wave propagation.
- Achieving ultra-wide bandwidth absorption in compact structures remains a significant challenge.
Purpose of the Study:
- To propose a new high-capacitive FSS structure for ultra-wide bandwidth absorbers.
- To design and validate a multilayer absorber with enhanced absorption capabilities.
Main Methods:
- Utilizing a novel folded spiral conductor FSS design for low-frequency resonance.
- Combining this with conventional FSS elements (square loop, square patch) for medium- and high-frequency resonance.
- Employing admittance analysis for optimization and validating through screen-printed sample measurements.
Main Results:
- Designed an ultra-wide absorption bandwidth from 4.7-50.0 GHz with a reflection loss below -10 dB.
- Achieved a compact total thickness of 7.0 mm, near the theoretical limit.
- Experimental results showed absorption from 5.2-44.0 GHz with a thickness of 6.5 mm, closely matching simulations.
Conclusions:
- The proposed folded spiral FSS is effective for creating compact, ultra-wide bandwidth absorbers.
- The design demonstrates excellent performance and good agreement between simulation and experimental validation.
- The study also discusses angular stability for TE and TM polarizations.
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