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1

Metamateriały, konfigurowalne matryce antenowe i komunikacja holograficzna – wstępna analiza nowej koncepcji bezprzewodowej transmisji danych

Kliks Adrian

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

|

2023

|

nr 4

29--39

PL

W ostatnich kilku latach bardzo duże zainteresowanie wśród naukowców z całego świata zdobywa niezwykle oryginalna koncepcja komunikacji holograficznej. Specyfika tego podejścia z jednej strony niezwykle mocno odbiega od znanych i stosowanych obecnie rozwiązań, z drugiej stwarza bardzo duże możliwości rozwojowe w zakresie komunikacji bezprzewodowej. W artykule w sposób przeglądowy przedstawiono dwa rozwiązania technologiczne, które stały się przyczyną powstania idei komunikacji holograficznej. Jako pierwsze opisano możliwość wykorzystania tzw. meta-materiałów dla celów bezprzewodowej transmisji danych, jako drugie natomiast – zastosowanie rekonfigurowalnych powierzchni antenowych. W ostatniej części przedstawiono z kolei założenia idei komunikacji holograficznej, w której znane z holografii optycznej zasady tworzenia obrazów zostały przeniesione do pasma radiowego i do pewnego stopnia uogólnione.

EN

In the last few years, a very original concept of holographic communication has gained a lot of interest among scientists from all over the world. The specificity of this approach, on the one hand, is very different from the known and currently used solutions, on the other hand, it creates great development opportunities in the field of wireless communication. The article provides an overview of two technological solutions that gave rise to the idea of holographic communication. First, the possibility of using the so-called meta materials for the purposes of wireless data transmission, and the second – the use of reconfigurable antenna surfaces. The last part presents the assumptions of the idea of holographic communication, in which the principles of creating images known from optical holography have been transferred to the radio band, and to some extend – generalized.

2

Sound transmission loss calculation for metamaterial plate using combined analytical and numerical approach

Chojnacka Klara, Kras Aleksander, Kamisiński Tadeusz

Vibrations in Physical Systems

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2022

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Vol. 33, nr 3

art. no. 2022314

EN

In recent years acoustic metamaterials are broadly investigated in many different fields of acoustics and one of them is noise and vibration mitigation. The solution with highest potential are locally resonant metamaterials (LRS), which by creation of band gap effect in flexural wave propagation in structure improve its Sound Transmission Loss (STL). Standard STL simulation procedures can be fully analytical or numerical. Analytical solution, when it comes to metamaterial modelling, is fast but it does not take into consideration metamaterial geometry. On the other hand numerical solution even when considering small part of periodic structure, is time consuming and can generate numerical errors related for example to the mesh. In this work combined analytical - numerical method is analysed as the alternative for STL calculation. This method can be a substitute for basic simulation procedures concerning vibro-acoustic metamaterials, since the simulations results are comparable and it is less time consuming method. Formulas and simulation procedure for the presented method are described and compared with analytical and numerical simulation results as well as with STL measurement results.

3

A review of modern materials used in military camouflage within the radar frequency range

Szczodrowska Bogusława, Mazurczuk Robert

Technical Transactions

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2021

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Vol. 118, iss. 1

art. no. e2021003

EN

The article presents an overview of materials which can be employed used to camouflage objects on the modern battlefield in the radar frequency range.

PL

W artykule przedstawiono przegląd materiałów możliwych do zastosowania w maskowaniu w zakresie radiolokacyjnym obiektów współczesnego pola walki.

4

Use of the waveguide technique to measure the electromagnetic parameters of materials

Budnarowska Magdalena, Mizeraczyk Jerzy

Scientific Journal of Gdynia Maritime University

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2020

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nr 115

7--13

EN

The paper presents and discusses selected simulation and measurement possibilities of an upgraded waveguide measuring stand for testing electromagnetic properties of selected materials (including metamaterials), based on the microwave propagation technique. The stand is equipped with the CST Studio Suite software, which enables modeling and simulation of broadly defined electromagnetic interactions, and the N1500A Materials Measurement Suite module for processing the results of measurements of electromagnetic properties of materials.

5

Simulation research on the electromagnetic properties of the ELC resonator in the microwave range

Budnarowska Magdalena, Mizeraczyk Jerzy

Scientific Journal of Gdynia Maritime University

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2020

|

nr 115

14--20

EN

The paper concerns modeling and simulation of the interaction of electromagnetic radiation with the metamaterial ELC resonator in the microwave range of 5 GHz to 10 GHz. The simulation was performed using the CST Studio software in the Student version. The result of the simulation is the frequency characteristics of the coefficients of absorption (A), transmission (T) and reflection (R) of the ELC resonator, as well as the values of the real and imaginary parts of electric and magnetic permeability coefficients of that structure. The results obtained suggest that the examined metamaterial structure of the ELC shows strong absorption properties of resonant nature.

6

Metamateriały elektromagnetyczne

Hausman Sławomir

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2019

|

nr 6

137--138

EN

Electromagnetic metamaterials are artificially engineered composites with designed properties not present in nature. Their applications range from reduced size antennas to invisibility cloaks.

7

Compact MIMO antenna design based on fractal geometry and DSG

Cao Thanh Nghia, Krzysztofik Wojciech Jan

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2019

|

nr 6

299-302, CD

EN

The paper presents a 2-port MIMO antenna, which is designed to operate in the 5.745 GHz band for WLAN systems. The antenna is designed based on a combination of fractal geometry and metamaterial structure to reduce its size and enhance its bandwidth. The microwave laminate FR4-epoxy with permittivity = 4.4, thickness h = 1.6mm and dielectric tangent loss 0.02 is used as an antenna substrate. The result of the design is a compact size MIMO antenna with an overall size of 30.4x13.4mm. MIMO antennas achieve high performance through the evaluation of criteria as Envelope of Correlation Coefficient, ECC, Total Active Reflection Coefficient, TARC, and Channel Capacity Loss, CCL. All of them satisfied well the WLAN-MIMO system requirements.

8

Design of a visible dual broadband nearly perfect absorber

Jia Xiuli

Optica Applicata

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2019

|

Vol. 49, nr 1

115--124

EN

Many optical systems benefit from elements that can absorb a broad range of wavelengths over a wide range of angles, independent of polarization. In this paper, we present a nearly perfect absorber with dual broadband and polarization-independent in the visible regime that exploits strong symmetric and asymmetric resonance modes of electromagnetic dipoles. It makes use of a bilayer hollowed-out cross pattern structure which is simple, having five layers that include two stacks of metal film with hollowed-out ribbon in cross patterns, two dielectric spacers, and a metal reflecting layer. Simulations show that the design exhibits a significantly enhanced absorption property when compared to a device with a normal cross pattern structure. The nearly perfect absorption efficiency of the device is above 98.5% at two resonances regimes: from 5.57 × 1014to 6.08 × 1014Hz and from 6.75 × 1014to 7.05 × 1014Hz, and its stable absorption characteristics can be maintained over a wide range of polarizing angle – up to ±90°. This strategy can, in principle, be applied to other material systems and could be useful in diverse applications, including thermal emitters, photovoltaics, and photodetectors.

9

Metamaterials in application for improving the parameters of antennas

Cao T. N., Krzysztofik W. J.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

|

2018

|

nr 6

300--303, CD

EN

In this paper, the metamaterials structure and some of its benefits in antenna design are presented. Metamaterials can be applied as defected ground structures, superstrates of antennas to enhance some parameters of the antenna such as bandwidth, gain or reduction in dimension. Depending on the values of permittivity and permeability to classify the metamaterials and apply them in the antenna design for different purposes. The metamaterial antennas are calculated and simulated based on commercial software such as CST Studio, HFSS.

10

Interaction of orthogonal-polarized waves in 1D metamaterial with kerr nonlinearity

Ampilogov D.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2017

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Vol. 21, No 2

149--163

EN

The investigation of the wave propagation in a 1D metamaterial is continued in this paper. A nonlinear evolution equation of the wave interaction of two polarizations by means of the projection operator method is obtained and a particular solution in the case of slow-varying envelopes is found.

11

General equation for directed electromagnetic wave propagation in 1D metamaterial: projectiong operator method

Ampilogov D., Leble S.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2016

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Vol. 20, No 2

143--155

EN

We consider a boundary regime problem for 1D wave propagation in a metamaterial medium with simultaneously negative dielectric permittivity and magnetic permeability. We apply a projecting operator method to the Maxwell system in the time domain that allows the space of the linear propagation problem to be split into subspaces of directed waves for the relations of a given material with general dispersion. After projection, the equations for directed waves have a maximally simplified form, which is most convenient for numerical and analytical integration. Matrix elements of the projectors act as integral operators. For a given nonlinearity and dispersion we derive a general system of interacting right/left waves with combined (hybrid) amplitudes. The result is specified for the Drude metamaterial model for both permittivity and permeability coefficients and the Kerr nonlinearity. We also discuss and investigate singular solitary wave solutions of the system as a limit stationary elliptic system related to some boundary regimes.

12

Analysis of a metal clad waveguide sensor having metamaterial as a guiding layer

Upadhyay A., Prajapati Y. K., Tripathi R., Singh V., Saini J. P.

Opto-Electronics Review

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2016

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Vol. 24, No. 2

47--57

EN

In this study a metal clad waveguide sensor with a metamaterial guiding layer is analyzed. Sensitivity of the proposed sensor is derived using dispersion and Fresenal’s equations for waveguiding mode and reflection mode. While efficiently analyzing and comparing the results with the existing one, some interesting findings are achieved. It is observed that the proposed sensor shows larger cover layer sensitivity and larger adlayer sensitivity compared to the dielectric guiding layer sensor due to adsorbtive properties of metamaterial. Henceforth, it concludes that the proposed sensor shows sensitivity improvement over a dielectric guiding layer sensor.

13

Sensitivity enhancement of metamaterial-based surface plasmon resonance biosensor for near infrared

Pal S., Prajapati Y. K., Saini J. P., Singh V.

Optica Applicata

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2016

|

Vol. 46, nr 1

131--143

EN

The present study investigates the angular response and sensitivity of a surface plasmon resonance biosensor with metamaterial, by taking the advantage of the remarkable property of metamaterials. The proposed biosensor numerically shows that silver with a metamaterial layer enhances the sensitivity. The thickness of metamaterial and silver layer has been optimized. On comparing these results with a conventional surface plasmon resonance biosensor, it is observed that the sensitivity of the proposed biosensor is improved by introducing the metamaterial. The proposed biosensor has a sensitivity 6.3124 times higher than that of the conventional surface plasmon resonance sensor.

14

Modeling and simulation of metamaterial-based devices for industrial applications

Bhattacharya A.

Elektronika : konstrukcje, technologie, zastosowania

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2016

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Vol. 57, nr 10

66--69

EN

Metamaterials offer great potential for the development of new technologies and to make existing devices smaller, faster and more efficient. Metamaterials produce electromagnetic phenomena that are not seen in natural materials, and come in a wide variety of types. When developing a new metamaterial, simulation can be used both to analyse both the bulk property of the material and individual element. This article will show how CST STUDIO SUITE can be used to simulate and design metamaterials through the entire workflow, from the design of the resonator to the implementation in a full device.

PL

Metamateriały dają ogromny potencjał dla rozwoju nowych technologii. Umożliwiają miniaturyzację, przyspieszają działanie i podnoszą wydajność urządzeń elektronicznych. W metamateriałach powstają zjawiska elektromagnetyczne, które nie występują w materiałach naturalnych. Istnieje szeroka gama typów metamateriałów. Przy opracowywaniu nowych typów duże znaczenie mają symulacje elektromagnetyczne. W symulacjach stosuje się zarówno analizę własności komórek elementarnych struktury, jak i analizę uśrednionych właściwości metamateriału. Artykuł prezentuje zastosowanie oprogramowania CST STUDIO SUITE do symulacji i analizy metamateriałów w całym procesie, od projektu elementarnego rezonatora do realizacji kompletnego urządzenia.

15

Isotropy analysis of metamaterials

Kalvach A., Szabó Z.

Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska

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2015

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nr 4

52--54

EN

Metamaterials – artificial periodic structures with subwavelength feature sizes – can be characterized with macroscopic electromagnetic properties, like refractive index and wave impedance, just like homogeneous materials. However, in contrast to homogeneous materials, their properties depend strongly on the angle of incidence. 3D metamaterial structures can exhibit homogeneous behaviour, but their fabrication is challenging compared to layered (2D) metamaterials. Here we demonstrate with an example, that layered (2D) metamaterials can also exhibit homogeneous behaviour despite of their anisotropic geometry.

PL

Metamateriały – sztuczne struktury periodyczne o wymiarze charakterystycznym porównywalnym z długością fali – można scharakteryzować za pomocą tych samych właściwości jak dla materiałów homogenicznych np. współczynnikiem załamania czy impedancją falową. Jednakże, w przeciwieństwie do materiałów homogenicznych, ic parametry silnie zależą od kąta padania fali. Trójwymiarowe struktury metamateriałów mogą wykazywać jednorodne zachowanie, ale ich wykonanie jest trudne w porównaniu do metamateriałów warstwowych (2D). W artykule pokazujemy na przykładzie, że metamateriały warstwowe (2D) mogą również wykazywać jednorodne zachowanie pomimo ich anizotropowej geometrii.

16

Photonic band gap in negative ternary refractive indices of two-dimensional photonic crystal

Gharaati A, Mohamadebrahimi L, Roozitalab Z

Optica Applicata

|

2014

|

Vol. 44, nr 4

637--648

EN

In this paper, we study propagation of electromagnetic wave in negative ternary refractive indices of two-dimensional photonic crystals. We consider two structures with two concentric cylindrical rod and shell in which one of them has negative refractive indices, in positive dielectric background. It is shown that by increasing the diameter of the rod in both structures, we can obtain more and wider band gaps in comparison with the structures in which there is no negative refractive index materials. This increase is more considerable in the first structure, in which the rod has a negative refractive index, in comparison with the second one, where the rod has a positive refractive index.

17

Metamaterials with negative compressibility – a novel concept with a long history

Imre A R

Materials Science Poland

|

2014

|

Vol. 32, No. 2

126--129

EN

Metamaterials with negative compressibility are a very promising group of novel materials with a wide variety of potential application. A recent model proposed construction of the structures with three-dimensional negative compressibility by utilizing successive destabilization of stable or metastable states and inducing phase transitions mimicking negative compressibility. Here, we would like to show that similar concept is used by the nature and a nice example of this kind of metamaterial can be seen even in a glass of water.

18

Wpływ typu przekładki na transmisję złożenia dwóch struktur binarnych

Szota M.

Inżynieria Materiałowa

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2014

|

Vol. 35, nr 6

548--551

PL

W pracy przedstawiono metody symulacji transmisji układów wielowarstwowych oraz zbadano wpływ zmiany typu oraz grubości warstwy materiału rozdzielającego dwie struktury wielowarstwowe. Do analizy wykorzystano metodę macierzową. Wykazano znaczący wpływ niejednorodności wykonania warstwy rozdzielającej (przekładki) na transmisję oraz znacznie mniejszy wpływ niedokładności wykonania grubości warstwy.

EN

The paper presents a simulation method of multilayers transmission and examines the impact of changes in the type and thickness of the material separating the two multilayer structures. For the analysis, the matrix method were used. It has been shown significantly influence the implementation of the separation layer inhomogeneities on the transmission and significantly lower thickness inaccuracies implementation.

19

The impact of manufacturing inaccuracies on the filtration properties of Thue-Morse aperiodic superlattice systems

Garus S., Gruszka K., Garus J., Błoch K., Nabiałek M., Dośpiał M., Szota M.

Inżynieria Materiałowa

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2014

|

Vol. 35, nr 2

117--120

EN

The paper presents the results of study of filtration properties of aperiodic multilayer systems constructed according to the Thue-Morse algorithm. The study consisted of electromagnetic wave propagation simulation in range of 300÷700 nm depending on the angle of incidence relative to the normal of superlattice's surface. First simulation of propagation for the ideal structure was performed in which the thickness of the individual layers were 150 nm, and then defects in the form of small variations in the thickness of the layer (in the range of ± 7%) were applied. The study revealed that the band gaps are highly correlated with the thicknesses of the individual layers, the type and arrangement of used material. With the increase in generation also increases the number of transmission bands, and their half-width decreases. Manufacture inaccuracies have small influence on the transmission maxima but strongly affect the interband spaces.

PL

W pracy przedstawiono wyniki badań właściwości filtracyjnych dla aperiodycznych układów wielowarstwowych zbudowanych zgodnie z algorytmem Thue-Morse’a. Badania polegały na symulacji propagacji fali elektromagnetycznej o długościach leżących w przedziale od 300÷700 nm w zależności od kąta padania względem normalnej do powierzchni badanej supersieci. Przeprowadzono symulację propagacji dla struktury idealnej, w której grubości poszczególnych warstw wynosiły 150 nm, a następnie wprowadzano defekty w postaci niewielkiej zmiany grubości warstw (w zakresie ±7%). Badania ujawniły, że przerwy pasmowe są silnie skorelowane z grubością poszczególnych warstw, typem użytego materiału oraz jego ułożeniem. Wraz ze wzrostem liczby generacji rośnie także liczba pasm transmisji, a ich szerokość połówkowa maleje. Niedokładności wytworzenia w niewielki sposób wpływają na maksima transmisji, ale silnie oddziałują na przestrzenie międzypasmowe.

20

Wpływ typu przekładki na transmisję złożenia dwóch struktur binarnych

Szota M.

Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska

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2014

|

nr 3

23--26

PL

W pracy przedstawiono metody symulacji transmisji układów wielowarstwowych oraz zbadano wpływ zmiany typu oraz grubości warstwy materiału rozdzielającego dwie struktury wielowarstwowe. Do analizy wykorzystano metodę macierzową. Wykazano znaczący wpływ niejednorodności wykonania warstwy rozdzielającej (przekładki) na transmisję oraz znacznie mniejszy niedokładności wykonania grubości warstwy.

EN

The paper presents a simulation method of multilayers transmission and examines the impact of changes in the type and thickness of the material separating the two multilayer structures. For the analysis, the matrix method were used. It has been shown significantly influence the implementation of the separation layer inhomogeneities on the transmission and significantly smaller of thickness inaccuracies implementation.