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Dielectric Resonator Antenna For X Band Microwave Application
International Journal of Advanced Research in Electrical, Electronics and Instrumentation Engineering , 2013,
Abstract: A simple Dielectric Resonator Antenna (DRA) for X band frequency operation is proposed in this paper. X band is a microwave band lies between frequency range 8 to 12 GHz. In proposed DRA reflector plane is used beneath the microstrip feed line with a small air gap, introduced between feed substrate and reflector plane to reduce the back lobe. Slot coupling is used to excite this DRA. Proposed DRA design gives dual band operation in X band and resonates at frequency 8.6 GHz and 10.3 GHz. Antenna design offers minimum return loss of -20.3 db and -24.5 db at 8.6 GHz and 10.3 GHz respectively. It also offers high front to back ratio (FBR) of 12.35db and 9.83 db at 8.65 GHz and 10.3 GHz respectively. Return loss impedance bandwidth of 390 MHz (4.5%) for Band I and 730MHz (7.3%) for band II is obtained. Simple DRA design with high FBR is proposed here for X band application that shows a total bandwidth of 11.8%. DRA is analysed using Ansoft HFSS based on finite element method. Radiation characteristics of this DRA are observed at resonating frequencies. This DRA is useful at microwave X band application such as satellite communication.
International Journal of Electronics and Communication Engineering And Technology (IJECET) , 2016,
Abstract: A novel design of rectangular microstrip antenna is realized for penta band operation from conventional rectangular microstrip antenna (CRMA) by loading slots on the conducting patch. The penta bands are achieved by incorporating four T- shaped slots along the length and width of CRMA. The magnitude of each operating bands spread over c to ku band of frequency spectrum are found to be 1.14%, 7.29%, 1.6%, 3.71% and 3.33% respectively. Further these penta bands can be converted to hexa bands by removing two T-shaped slots along the length of CRMA without changing the nature of radiation characteristics. The magnitude of each operating band is found to be 2.70 %, 5.82 %, 12.15 %, 3.45 %, 7.30 % and 7.13 % respectively. The proposed antennas may find application in microwave communication systems operating at c to ku bands.
Metamaterials for Wireless Communications, Radiofrequency Identification, and Sensors  [PDF]
Ferran Martín
ISRN Electronics , 2012, DOI: 10.5402/2012/780232
Abstract: This paper is focused on the application of concepts derived from metamaterials to the development of novel devices, circuits, and antennas of interest in wireless communications, radiofrequency identification (RFID), and sensors. Specifically, it is shown that artificial transmission lines based (or inspired) on metamaterials exhibit interesting properties, useful for the implementation of high-performance and compact devices as well as novel functional devices. Thanks to the presence of reactive loading elements in such artificial lines, the main line parameters, that is, the characteristic impedance and the phase constant, can be engineered. This has opened new paths for RF and microwave circuit and antenna design on the basis of impedance and dispersion engineering. 1. Introduction With the beginning of the century and the millennium, a new research field appeared in the scene of Science and Technology:??Metamaterials. Indeed, the number of journal and conference papers, special sessions in conferences, and research and development projects and contracts related to metamaterials has experienced an exponential growth since 2000. Metamaterials can be considered a transversal topic, involving many different disciplines and fields, such as acoustics, electromagnetism, RF and microwave engineering, millimeter wave and THz technology, micro- and nanotechnology, photonics and optics, and medical engineering, among others. During the last years, several books devoted to metamaterials have been published by active researches in the field [1–9]. Such books cover different aspects of metamaterial science and technology, including theory, technology, and applications. In this paper, the focus is on the applications of metamaterial concepts to the design of RF/microwave devices for wireless applications, radiofrequency identification (RFID), and sensors. Therefore, we recommend the reader the books [1–3, 6, 8] for an in-depth treatment of some of the concepts and applications included in this paper, since these books are mainly devoted to electromagnetic metamaterials. Metamaterials are artificial materials, made of periodic inclusions (or “atoms”) of conventional materials (metals and dielectrics) with controllable electromagnetic (or acoustic, or optical) properties. In these artificial materials, the period is much smaller than the guided wavelength; therefore, the structure behaves as a homogeneous (continuous) medium, exhibiting effective medium properties. Such properties can be controlled by properly engineering or structuring the material, and they can
MM-Wave Metamaterial Adjustable Antenna on Magnetically Biased Ferritic Substrate  [PDF]
Gheorghe Sajin,Iulia Andreea Mocanu,Florea Craciunoiu
International Journal of Antennas and Propagation , 2013, DOI: 10.1155/2013/696483
Abstract: The paper presents a mm-wave metamaterial coplanar waveguide (CPW) zeroth-order resonating (ZOR) antenna on magnetically biased ferrite substrate. The measurements demonstrate tuning of the resonant frequency and steering of the radiation characteristic depending on the strength of biasing magnetic field. The resonant frequency shifts about 1.1?GHz for magnetic biasing field strength variation between 0?T and 0.265?T. The return loss is reduced as result of elimination of ferrite low field loss. The radiation characteristic in transversal plane steers between approximately ?15° and +14° depending on the magnetic field strength. In the magnetically unbiased state the antenna gain is 4.16?dBi and increases slightly to 4.22?dBi due to small field loss reduction following the magnetic polarization application. 1. Introduction In recent years area of metamaterials has been getting a lot of attention from the scientific community. Although Veselago enunciated the theory of left-handed (LH) materials more than 50 years ago [1], structures mimicking these properties were developed only about 12 years ago [2]. In the microwave and mm-wave frequency domain, metamaterials were introduced as the concept of composite right/left-handed transmission lines (CRLH-TL) [3]. Such a transmission line exhibits both right-handed (RH) and left-handed (LH) behavior depending on the frequency domain. This particular frequency characteristic of the CRLH-TL has been exploited in the development of many types of microwave and mm-wave devices, among them various types of antennas. A comprehensive description of the most practical leaky wave and zeroth-order resonating (ZOR) antennas was done in [4]. A special class of microwave and millimeter wave CRLH components consists of devices supported on magnetically biased ferrite. In literature there are very few contributions concerning this class of devices. A metamaterial antenna on magnetically biased ferritic material in microwave frequency domain ( ?GHz), demonstrating tuning capabilities of ?MHz and a radiation lobe steering of about ±10° was reported in literature [5–7]. Based on this previous experience we present the properties of a CRLH coplanar waveguide (CPW) ZOR antenna in the mm-wave frequency domain (30?GHz), having magnetically biased ferrite as substrate. This is, upon the authors’ knowledge, the first millimeter wave CRLH antenna on ferrite substrate reported for effective use in mm-wave integrated circuits. 2. Resonant CRLH Antenna Structure The analyzed device is a ZOR CRLH antenna composed of an open-ended array of

Yan Dunbao,Yuan Naichang,Zhang Guangfu,Fu Yunqi,

电子与信息学报 , 2003,
Abstract: In communication systems, the application of microstrip active antenna is useful for the simplification and downsizing of the system. But because the antenna is integrated with active devices, the harmonics produced by the active devices can result in the spurious radiation of the antenna. In this paper, the application of PBG(Photonic Band-Gap) structure to the active antenna is studied, and the calculated result and experimental result all indicate that the application of PEG structure can drastically diminish the radiation of harmonics, so the performance of system is improved.
Ultrathin microwave absorbers made of mu-near-zero metamaterials  [PDF]
Shuomin Zhong,Sailing He
Physics , 2012,
Abstract: In this paper, mu-near-zero (MNZ) metamaterials are utilized to achieve an ultrathin absorber with a thickness of only about one percent of the operating wavelength. The metamaterial absorber (MA) is made of double-layered metallic spiral arrays designed to have a large purely imaginary permeability at low microwave frequencies (~ 1.7 GHz). An absorption efficiency above 90% is demonstrated at illumination angles up to 60 degrees. A polarization-insensitive MA implemented by 2D isotropic metamaterials is also studied. Our designs have great application potential as compared with the traditional heavy and thick absorbers made of natural materials working at the same frequencies.
Reconfigurable photoinduced metamaterials in the microwave regime  [PDF]
Carlo Rizza,Alessandro Ciattoni,Francesco De Paulis,Elia Palange,Antonio Orlandi,Lorenzo Columbo,Franco Prati
Physics , 2014, DOI: 10.1088/0022-3727/48/13/135103
Abstract: We investigate optically reconfigurable dielectric metamaterials at gigahertz frequencies. More precisely, we study the microwave response of a subwavelength grating optically imprinted into a semiconductor slab. In the homogenized regime, we analytically evaluate the ordinary and extraordinary component of the effective permittivity tensor by taking into account the photo-carrier dynamics described by the ambipolar diffusion equation. We analyze the impact of semiconductor parameters on the gigahertz metamaterial response which turns out to be highly reconfigurable by varying the photogenerated grating and which can show a marked anisotropic behavior.
Elliptic Cylinder with Slotted Antenna Coated with Magnetic Metamaterials  [PDF]
A. K. Hamid
International Journal of Antennas and Propagation , 2011, DOI: 10.1155/2011/842863
Abstract: The radiation properties of an axially slotted elliptic antenna coated with magnetic metamaterials are investigated. The fields inside and outside the dielectric coating are expressed in terms of the Mathieu functions. The boundary conditions at various surfaces are enforced using the orthogonality property of angular Mathieu functions. Numerical results are presented graphically for the radiation pattern, aperture conductance, and antenna gain for the TM case. It was found that a slotted antenna coated with magnetic metamaterials has more gain as well as lower side lobes compared to one coated with conventional dielectric or nonmagnetic metamaterials. 1. Introduction Radiation properties of an axially slotted antenna are very important in communications and airplane industries. Numerous authors in the literature have investigated the radiation by dielectric-coated slotted circular and elliptical cylinders. For example, Hurd [1] studied the radiation pattern of a dielectric axially slotted cylinder. The external admittance of an axial slot on a dielectric-coated metal cylinder was investigated by Knop [2]. Shafai [3] obtained the radiation properties of an axially slotted antenna coated with a homogenous material. Wong [4, 5] investigated the radiation properties of slotted cylinder of elliptical cross-section while Richmond [6] studied the radiation from an axial slot antenna on a dielectric-coated elliptic cylinder. The analysis was later extended to the radiation by axial slots on a dielectric coated nonconfocal conducting elliptic cylinder by Ragheb et al. [7]. Hussein and Hamid [8] studied the radiation by axially slotted cylinders of elliptical cross section coated with a lossy dielectric material. Recently, A. K. Hamid investigated the radiation characteristics of slotted circular or elliptical cylinder coated with lossy and lossless metamaterials [9, 10]. Lately, materials possessing both lossy and lossless metamaterials as well as chiral media have gained considerable attention in many researches [11–24]. In this paper, a theoretical analysis based on a boundary value solution for the case of antenna radiation by an axial slot on a conducting elliptic cylinder coated with magnetic metamaterials is presented. The fields inside and outside the dielectric coating are expressed in terms of radial and angular Mathieu functions. Numerical results are presented for the radiation pattern, aperture conductance, and antenna gain versus coating thickness as well as compared with conventionally dielectric-coated, magnetic and nonmagnetic
Axially Slotted Antenna on a Circular or Elliptic Cylinder Coated with Metamaterials
Abdul-Kadir Hamid
PIER , 2005, DOI: 10.2528/PIER04082301
Abstract: The radiation properties of an axially slotted circular or elliptical antenna coated with metamaterials are investigated. The fields inside and outside the dielectric coating are expressed in terms of Mathieu functions. The boundary conditions at various surfaces are enforced to obtain the unknown field expansion coefficients. Numerical results are presented graphically for the radiation pattern, aperture conductance and antenna gain for the TM case. It was found that slotted antenna coated with metamaterials has more directive beam with lower sidelobes compared to coated with conventional dielectric material.
Patch Antenna Based on Metamaterials for a RFID Transponder
E. Ugarte-Munoz,F. J. Herraiz-Martinez,V. Gonzalez-Posadas,D. Segovia-Vargas
Radioengineering , 2008,
Abstract: In this paper a self-diplexed antenna is proposed for a RFID transponder application. The development cycle is divided into two stages: antenna design and filters design. The antenna is based on a square microstrip patch filled with metamaterial structures. The inclusion of these structures allows simultaneous operation over several frequencies, which can be arbitrarily chosen. The antenna working frequencies are chosen to be 2.45 GHz (receiver) and 1.45 GHz (transmitter). In addition, the antenna is fed through two orthogonal coupled microstrip lines, what provides higher isolation between both ports. Some filters based on metamaterial particles are coupled or connected to the antenna feeding microstrip lines to avoid undesired interferences. This approach avoids using of an external filter or diplexer, providing larger size reduction and a compact self-diplexed antenna.
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