Metamaterial-based radiating and absorbing structures I

14:00 Invited talk : Multiple-band and broadband terahertz absorbers using multi-layered metallic structures

Shuo Liu, Di Bao, Tiejun Cui

Southeast University (China)

We present the simulation and measurement results for a multi-band absorber and broadband absorber at terahertz frequency. The quad-band absorber is composed of four metallic square loops averagely located on two polymide layers. It experimentally exhibits four absorption peaks with absorptivity over 98.5 percent. The broadband absorber is formed by averagely stacking 12 metallic sticks with varying lengths on three PI layers. The measured absorptivity totally exceeds 95 percent from 0.81 to 1.32 THz and the FWHM is 60 percent.
PDF file

14:20 Invited talk : Metamaterials for Antennas and RCS Reduction Structures

Juan Carlos Iriarte, Amagoia Tellechea, Inigo Ederra, Ramon Gonzalo

Public University of Navarra (Spain)

A lot of designs can be found in literature showing metamaterials possibilities and their application. However, the number of designs which comply with specifications of tangible applications have been limited. A review of the designs realized by Antenna Group of UPNa is presented in the paper, focusing in covering specific applications requirements. The designs take advantage of diverse properties of metamaterials (as EBGs and AMC) complying with specifications of real applications showing them as alternatives to conventional technology designs.
PDF file

14:40 Invited talk : Mobile phone model with metamaterials to reduce the exposure

Yenny Pinto, Xavier Begaud

ESPCI ParisTech (France)

This paper presents a terminal mobile model where an Inverted F Antenna (IFA) is associated with three different metamaterials: Artificial Magnetic Conductor (AMC), Electromagnetic Band-Gap (EBG) and Resistive High Impedance Surface (RHIS). The objective is to evaluate what is the metamaterial which is the best solution to reduce exposure. The exposure has been evaluated using a simplified phantom model. Results show that a reduction of 7.9 percent in SAR 10g is obtained using a RHIS structure.
PDF file

15:00 Invited talk : 2-SR-based electrically small antenna for RFID applications

Ferran Paredes, Simone Zuffanelli, Pau Aguila, Gerard Zamora, Ferran Martin, Jordi Bonache

Universitat Autonoma de Barcelona (Spain)

In this work the 2-turns Spiral Resonator (2-SR) is used as an electrically small antenna for passive Radio Frequency IDentification (RFID) tags at the Ultra-High Frequency band (UHF). The radiation properties are analyzed to explore the advantages and limitations of the 2-SR applied to the tag antenna design. As a proof of concept, a passive tag based on the 2-SR was designed, fabricated and the read range was measured, obtaining distances of roughly 5.5 meters.
PDF file

15:20 Invited talk : Towards the Analytical Design of Bianisotropic Metasurfaces

Nikolaos Chiotellis, Anthony Grbic

University of Michigan (USA)

In this work, metasurfaces exhibiting bianisotropic responses are synthesized using analytical models. Such metasurfaces can be implemented by cascading patterned metallic claddings and electrically thin dielectric substrates. Simple expressions for the sheet impedance of periodic claddings are found for arbitrarily incident plane waves in the long wavelength regime. Using the derived models, an X-band polarization rotator is designed analytically, and tuned within a full-wave solver to achieve optimal performance.
PDF file

15:40 Invited talk : A Multilayer Metasurface Cloak Coating for Monopole Antennas

Zhi Hao Jiang, Douglas Werner

The Pennsylvania State University (USA)

A multilayer metasurface cloak coating is introduced for monopole antennas. It retains the input impedance and radiation parameters of the antenna for its original operational band. At the same time, it also reduces the monopole's scattering signature and the received power for the operational band of another system located in close proximity. The coating, consisting of two layers of concentric anisotropic metasurfaces, is designed by tailoring their dispersive electromagnetic properties.
PDF file