scholarly journals Simple, Compact, and Multiband Frequency Selective Surfaces Using Dissimilar Sierpinski Fractal Elements

2015 ◽  
Vol 2015 ◽  
pp. 1-5 ◽  
Author(s):  
Clarissa de Lucena Nóbrega ◽  
Marcelo Ribeiro da Silva ◽  
Paulo Henrique da Fonseca Silva ◽  
Adaildo Gomes D’Assunção ◽  
Gláucio Lima Siqueira
Keyword(s):  
High Frequency ◽  
Design Methodology ◽  
Frequency Tuning ◽  
Microstrip Antennas ◽  
Frequency Selective Surfaces ◽  
Experimental Characterization ◽  
Spatial Filters ◽  
Frequency Responses ◽  
Frequency Selective

This paper presents a design methodology for frequency selective surfaces (FSSs) using metallic patches with dissimilar Sierpinski fractal elements. The transmission properties of the spatial filters are investigated for FSS structures composed of two alternately integrated dissimilar Sierpinski fractal elements, corresponding to fractal levelsk=1, 2, and 3. Two FSS prototypes are fabricated and measured in the range from 2 to 12 GHz to validate the proposed fractal designs. The FSSs with dissimilar Sierpinski fractal patch elements are printed on RT/Duroid 6202 high frequency laminate. The experimental characterization of the FSS prototypes is accomplished through two different measurement setups composed of commercial horns and elliptical monopole microstrip antennas. The obtained results confirm the compactness and multiband performance of the proposed FSS geometries, caused by the integration of dissimilar fractal element. In addition, the proposed FSSs exhibited frequency tuning ability on the multiband frequency responses. Agreement between simulated and measured results is reported.

scholarly journals Continuous-range tunable multilayer frequency-selective surfaces using origami and inkjet printing

2018 ◽  
Vol 115 (52) ◽  
pp. 13210-13215 ◽  
Author(s):  
Syed Abdullah Nauroze ◽  
Larissa S. Novelino ◽  
Manos M. Tentzeris ◽  
Glaucio H. Paulino
Keyword(s):  
Low Cost ◽  
Frequency Selective Surfaces ◽  
Angle Of Incidence ◽  
Spatial Filters ◽  
Continuous State ◽  
Subtractive Manufacturing ◽  
Time Requirements ◽  
Frequency Selective ◽  
Tunable Frequency ◽  
Electrical Components

The tremendous increase in the number of components in typical electrical and communication modules requires low-cost, flexible and multifunctional sensing, energy harvesting, and communication modules that can readily reconfigure, depending on changes in their environment. Current subtractive manufacturing-based reconfigurable systems offer limited flexibility (limited finite number of discrete reconfiguration states) and have high fabrication cost and time requirements. Thus, this paper introduces an approach to solve the problem by combining additive manufacturing and origami principles to realize tunable electrical components that can be reconfigured over continuous-state ranges from folded (compact) to unfolded (large surface) configurations. Special “bridge-like” structures are introduced along the traces that increase their flexibility, thereby avoiding breakage during folding. These techniques allow creating truly flexible conductive traces that can maintain high conductivity even for large bending angles, further enhancing the states of reconfigurability. To demonstrate the idea, a Miura-Ori pattern is used to fabricate spatial filters—frequency-selective surfaces (FSSs) with dipole resonant elements placed along the fold lines. The electrical length of the dipole elements in these structures changes when the Miura-Ori is folded, which facilitates tunable frequency response for the proposed shape-reconfigurable FSS structure. Higher-order spatial filters are realized by creating multilayer Miura-FSS configurations, which further increase the overall bandwidth of the structure. Such multilayer Miura-FSS structures feature the unprecedented capability of on-the-fly reconfigurability to different specifications (multiple bands, broadband/narrowband bandwidth, wide angle of incidence rejection), requiring neither specialized substrates nor highly complex electronics, holding frames, or fabrication processes.

scholarly journals Discretely assembled mechanical metamaterials

2020 ◽  
Vol 6 (47) ◽  
pp. eabc9943
Author(s):  
Benjamin Jenett ◽  
Christopher Cameron ◽  
Filippos Tourlomousis ◽  
Alfonso Parra Rubio ◽  
Megan Ochalek ◽  
...  
Keyword(s):  
Design Methodology ◽  
Best Practice ◽  
Low Cost ◽  
Experimental Characterization ◽  
Cell Geometry ◽  
Mechanical Metamaterials ◽  
Global Configuration ◽  
Finite Set ◽  
Monolithic Structures

Mechanical metamaterials offer exotic properties based on local control of cell geometry and their global configuration into structures and mechanisms. Historically, these have been made as continuous, monolithic structures with additive manufacturing, which affords high resolution and throughput, but is inherently limited by process and machine constraints. To address this issue, we present a construction system for mechanical metamaterials based on discrete assembly of a finite set of parts, which can be spatially composed for a range of properties such as rigidity, compliance, chirality, and auxetic behavior. This system achieves desired continuum properties through design of the parts such that global behavior is governed by local mechanisms. We describe the design methodology, production process, numerical modeling, and experimental characterization of metamaterial behaviors. This approach benefits from incremental assembly, which eliminates scale limitations, best-practice manufacturing for reliable, low-cost part production, and interchangeability through a consistent assembly process across part types.

Composite Right/Left Handed based Frequency Selective Surfaces for enhancement in performance of microstrip antennas

2016 ◽  
Author(s):  
Karthik Thothathri Chandrasekaran ◽  
Muhammad Faeyz Karim ◽  
Nasimuddin ◽  
Arokiaswami Alphones ◽  
Leong Siew Weng ◽  
...  
Keyword(s):  
Microstrip Antennas ◽  
Frequency Selective Surfaces ◽  
Left Handed ◽  
Frequency Selective

Experimental characterization of graphene by electrostatic resonance frequency tuning

2017 ◽  
Vol 122 (23) ◽  
pp. 234302 ◽  
Author(s):  
Banafsheh Sajadi ◽  
Farbod Alijani ◽  
Dejan Davidovikj ◽  
Johannes (Hans) Goosen ◽  
Peter G. Steeneken ◽  
...  
Keyword(s):  
Resonance Frequency ◽  
Frequency Tuning ◽  
Experimental Characterization

Experimental characterization of fundamental and second harmonic beams for a high-frequency ultrasound transducer

2002 ◽  
Vol 28 (5) ◽  
pp. 635-646 ◽  
Author(s):  
Emmanuel W Cherin ◽  
Jens Kristian Poulsen ◽  
A.F.W van der Steen ◽  
Paul Lum ◽  
F.Stuart Foster
Keyword(s):  
High Frequency ◽  
Second Harmonic ◽  
Ultrasound Transducer ◽  
Experimental Characterization ◽  
High Frequency Ultrasound ◽  
Frequency Ultrasound
Sign in / Sign up

Export Citation Format

Share Document