Perfect Metamaterial absorber based energy harvesting application in ISM Band

An electromagnetic (EM) energy harvesting application based on metamaterial absorber (MA) is introduced and discussed in this paper. This application is operating at ISM band (2.40 GHz) which is especially chosen due to its wide usage area. Square ring resonator (SRR) which has two gaps and resistors across the gaps on it is used. Chips resistors are used to deliver power to any active component. Transmission and reflection characteristics of metamaterial absorber (MA) for energy harvesting application are investigated. 83.6% efficient for energy harvesting application is realized in this study

Perfect Metamaterial absorber based energy harvesting application in ISM Band

An electromagnetic (EM) energy harvesting application based on metamaterial absorber (MA) is introduced and discussed in this paper. This application is operating at ISM band (2.40 GHz) which is especially chosen due to its wide usage area. Square ring resonator (SRR) which has two gaps and resistors across the gaps on it is used. Chips resistors are used to deliver power to any active component. Transmission and reflection characteristics of metamaterial absorber (MA) for energy harvesting application are investigated. 83.6% efficient for energy harvesting application is realized in this study

Some aspects of mass-energy equivalence which appears in left-handed metamaterials

In this work, the concept of mass-energy equivalence in left-handed metamaterials is discussed by following Einstein's box thought experiment. Left-handed metamaterials are artificial composite structures that exhibit unusual properties, especially negative refractive index, in which phase and group velocities are directed oppositely. Equation E = mc2 assumes that, in vacuum, the propagation of an electromagnetic radiation from emitter to receiver is accompanied by the transfer of mass. It was hypothesized previously that if the space between emitter and receiver is medium with a negative refractive index, then radiation transfers the mass not from the emitter to receiver as expected, but rather from the receiver to the emitter due to the opposite directions of phase and group velocities. In this paper, it is shown that even though one radiating atom is taken, the negative mass transferring must be in force. In particular, it means that, if the atom radiates a photon in a medium with negative refractive index, photon transfers the mass not from the atom, but to the atom

Octagonal Shaped Metamaterial Absorber Based Energy Harvester

In this study, a novel octagonal shaped metamaterial based broadband absorber is proposed for energy harvesting at WIMAX wireless communication band. The proposal has an absorption of 99.97 % at 5.5 GHz with a bandwidth of 1 GHz between 5 GHz and 6 GHz in Transverse Electric (TE) mode. Transverse Electric (TE), Transverse Magnetic (TM) and Transverse Electromagnetic (TEM) modes are studied numerically in this paper. In TM and TEM modes, proposed structure has absorption of nearly 96 % and 98 % respectively at 6 GHz. The proposed structure is polarization angle independent which is important for energy harvesting applications. Energy harvesting application is realized by using resistive loads on the design, simulations are parametrically studied on resistive loads and experimental study is realized for reflection coefficient measurement and compared with simulated results. Both experimental and simulated results are complying with each other. The proposed structure has different usage areas in stealth areas, detection and imaging. DOI: http://dx.doi.org/10.5755/j01.ms.24.3.18625</p

Negatif kırılma indisli meta-malzemelerin elde edilmesi

TEZ7468Tez (Doktora) -- Çukurova Üniversitesi, Adana, 2009.Kaynakça (s.110-116) var.x, 117 s. : res. ; 29 cm.In this thesis, using Finite Element Method based structure simulator HFSS, artificial media composed of different type of inclusions which are assigned as PEC provided negative electric and magnetic properties in microwave frequency region. Effects of unit cell dimensions on electromagnetic parameters are investigated. The results are obtained in terms of scattering parameters and by extraction the permittivity (? ) and permeability (? ) of artificial media have been founded. Increasement of diamagnetic effect has been provided by placing different value lumped capacitance to splits and spaces of SRRs. The permittivity and permeability of artificially designed planar and non planar type of media have been realized negative value, simultaneously. It is observed that this type of media shows negative refraction (- n ) and negative phase velocity (- p v ). Using TSSRR type inclusions in a rectangular waveguide, it has been achieved to transmit below cutoff frequency and so it has been made possible to decrease dimensions of waveguide.Bu tezde, FEM metodu tabanlı HFSS simülatörü kullanılarak farklı geometrik şekillerdeki MEİ özelliğine sahip birim elemanlardan oluşan yapay ortamların mikrodalga frekans aralığında elektriksel (? ) ve manyetik (? ) özelliklerinin negatif olması sağlanmıştır. Ortamı oluşturan birim hücrelerin ebatlarının ortamın elektromanyetik özelliklerine etkileri incelenmiştir. Veriler saçılma parametreleri (Sij) cinsinden elde edilmiş, bu parametrelerden çıkartma sureti ile elde edilen dielektrik ve manyetik katsayılarında yerlerine konularak ortam parametreleri hesaplanmıştır. Manyetik etkinin arttırılabilmesi için AHR yapıların değişik kısımlarına farklı kapasite değerlerindeki kondansatörler yerleştirilerek sonuçları gözlenmiştir. Düzlemsel ve düzlemsel olmayan şekilde tasarlanan yapıların elektromanyetik özelliklerini temsil eden dielektrik katsayı ve manyetik geçirgenliklerinin eş zamanlı negatif olması sağlanmıştır. Yapay olarak elde edilen bu malzemeler kullanılarak negatif kırılma (- n ) v e n egatif f az h ızı ( - p v ) sağlanabileceği gözlenmiştir. Dikdörtgensel bir dalga kılavuzu içerisine yerleştirilmiş manyetik metamalzeme kullanılarak ortamın manyetik özelliğinin negatif olması sağlanmış, böylece dalga kılavuzunun kesim frekansının altında iletim yapması ve dalga kılavuzu ebatlarının azaltılması mümkün olmuştur.Bu çalışma Ç.Ü. Bilimsel Araştırma Projeleri Birimi Tarafından Desteklenmiştir. Proje No:FEF2006D2

Design And Simulation Analysıs Of A Textıle Based Metamaterial Perfect Absorber For Energy Harvesting Applications At Wifi Band

Metamaterials, which are called as left-handed materials, exhibit electromagnetic properties that do not exist in nature, such as negative refractive index and reverse Doppler effect, at the frequency range for which they are designed. These unique properties of metamaterials have made them indispensable in a wide variety of applications such as sensor applications, signal absorption, antenna, and energy harvesting. In this study, the design and analysis of a metamaterial (MTM) perfect absorber at 5 GHz frequency band were performed to investigate the usability of the proposed structure in energy harvesting applications. The results of the study revealed that the proposed MTM structure has potentials to be used in energy harvesting applications

Design and analysis of perfect metamaterial absorber in GHz and THz frequencies

The new perfect metamaterial absorber (MA) based on square resonator with gap configuration is numerically (for GHz and THz frequency regime) and experimentally (for GHz frequency regime) presented and investigated. The proposed MA has a simple configuration which introduces flexibility to adjust its metamaterial properties and easily rescale the structure for other frequency regimes. In addition, polarization and incident angle independencies of the proposed model are analyzed for the THz frequency regime. The suggested structure could achieve very high absorption at wide angles of polarization and incident angles for both transverse electric and transverse magnetic waves. At resonance frequencies, absorption results are realized around 99.99% at 5.48GHz and 99.92% at 0.865THz for their respective frequency regimes. Besides numerical results in GHz and THz frequencies, experimental results are also obtained for GHz frequency regime. The proposed MA and its variations enable myriad potential applications in areas such as defense systems, communication, stealth technologies, and so on

Investigation of electromagnetic shielding properties of metal composite tufted carpets

WOS: 000477541300001In this research, it is aimed to develop tufted carpets with electromagnetic shielding (EMSE) effectiveness. For this purpose, stainless steel, copper, silver wires, and metalized silver PA filaments were commingled with textured polyester yarn to produce composite yarn. Composite yarns were used in tufted carpet backing fabric with different densities and directions. The EMSE of carpet samples was measured in the frequency range of 0.8-5.2 GHz by free space technique. The effects of metal type, composite yarn density, and placement direction on the EMSE were statistically analyzed in 0.8-3.0 and 3.0-5.2 GHz frequency ranges separately. Stainless steel and silver wires provided better EMSE in the range of 0.8-3.0 GHz. Stainless steel showed better EMSE in lower frequencies than 3 GHz. The metallized silver was more effective above 3 GHz. The increase in metal density significantly increased EMSE for all metal types. Carpets containing metal in two directions provided multidirectional shielding and maximum EMSE reached up to 44 dB level. As a result of the study, tufted carpets which can provide multi-axial protection were produced successfully

The Effect of Length of TSSRRs Loaded Substrate on WG Miniaturization

Abstract In this study, the effect of uniaxial anisotropic magnetic artificial media composed of TSRRs type magnetic dipoles on a rectangular waveguide-WR90 have been observed. Different length and number of TSRRs have been placed in WR90 and effect of reflection coefficient have been observed. Miniaturization of rectangular waveguides with artificial diamagnetic media and subwavelength propagation has been proved experimentally