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Antennas and Propagation, IEEE Transactions on

Issue 9 • Date Sept. 2012

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  • Table of contents

    Publication Year: 2012 , Page(s): C1 - 4026
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  • IEEE Transactions on Antennas and Propagation publication information

    Publication Year: 2012 , Page(s): C2
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  • Microstrip-Fed Monopole Antennas Loaded With CRLH Unit Cells

    Publication Year: 2012 , Page(s): 4027 - 4036
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2771 KB) |  | HTML iconHTML  

    The theory and implementation of a new family of monopole antennas loaded with composite right/left handed (CRLH) unit cells are presented. The proposed antennas have a number of narrow bands that is twice the number of unit cells and one wide band that is centered around the monopole original frequency. The new operating frequencies are below the original one and they are controlled by the unit cell dispersion relation. The proposed antennas occupy the same Chu sphere as the original monopole, all the operating frequencies have omni-directional radiation patterns, and matching is better than -10 dB. Three antennas are realized; the first is loaded with one distributed CRLH unit cell, the second is loaded with lumped components CRLH unit cell, and the third is loaded with two CRLH unit cells. All proposed antennas are fabricated and measured. Measurements and EM simulations confirm the proposed theory. View full abstract»

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  • Compact Azimuthal Omnidirectional Dual-Polarized Antenna Using Highly Isolated Colocated Slots

    Publication Year: 2012 , Page(s): 4037 - 4045
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2315 KB) |  | HTML iconHTML  

    An omnidirectional dual-polarized antenna with high port isolation is presented for 2.4-GHz wireless local area network (WLAN) applications. The omnidirectional patterns of both vertical and horizontal polarizations in the azimuthal plane are achieved by positioning two orthogonal slots cut onto the walls of a slender columnar cuboid. The overall volume of the proposed antenna is only 83 × 11 × 11mm3 (0.664λ0 × 0.088λ0 × 0.088λ0), with low mutual coupling between two radiating slots. A prototype of the proposed antenna is fabricated and tested. The measured results show that the 10-dB reflection coefficient bandwidths of dual polarizations cover the desired band of 2.4-2.48 GHz and the port isolation is lower than -33.5 dB. Stable gains are greater than 3.17 and 1.19 dBi for vertical and horizontal polarizations, respectively. The diversity performance is also evaluated, including the correlation coefficient, mean effective gain (MEG) ratio, and diversity gain. View full abstract»

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  • High-Isolation XX-Polar Antenna

    Publication Year: 2012 , Page(s): 4046 - 4055
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2458 KB) |  | HTML iconHTML  

    A new configuration of the dual-band and dual-polarized antenna is presented, which is fed by aperture coupling for the existing mobile communication systems working over 870-960 MHz (GSM) and 1710-2180 MHz (DCS/UMTS) frequency band. XX-Polar antenna stands for an antenna with dual-band and dual linear slant polarization. In this paper DU band stands for DCS/UMTS band. Measurement results show that the proposed antenna yields good broadside radiation characteristics including symmetric radiation patterns, low cross-polarization level ( <; -14 dB), low backlobe level (F/B >; 20 dB) and high isolation (>; 30 dB) at both bands. The designed antenna has an impedance bandwidth of 20.4% (790-970 MHz) for VSWR <; 1.5 in the lower band and 29.3% for VSWR <; 1.6 (1630-2190 MHz) in the upper band. The measured average gains are about 9.3-10.2 and 8.6-10 dBi in the lower and upper band, respectively. It is also promising for array antenna in various wireless systems. View full abstract»

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  • Passive UHF RFID Tag for Heat Sensing Applications

    Publication Year: 2012 , Page(s): 4056 - 4064
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2657 KB) |  | HTML iconHTML  

    A possible method of utilizing paraffin wax as a substrate material in developing a threshold heat sensing radio frequency identification (RFID) tag is discussed. A small narrowband passive UHF RFID tag is made on top of a multilayer substrate. Paraffin wax acts as the main heat sensitive layer of the substrate. The properties and characteristics of the paraffin layer change due to heat. The narrowband tag on top of the substrate is designed to be sensitive enough to detect any structural and physical changes of the substrate material. The changes in the properties of the substrate material will cause a shift in the operating frequency of the tag. This frequency shift will reduce the performance of the narrowband RFID sensor tag. The change in the properties of paraffin wax after being exposed to heat is irreversible under normal conditions and therefore, the proposed RFID tag can be referred to as a threshold heat sensing device. Such a low-cost solution can be useful in detecting heat exposures in various supply chains and transportation mishandling of heat sensitive items. View full abstract»

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  • Non-Uniform Metasurface Luneburg Lens Antenna Design

    Publication Year: 2012 , Page(s): 4065 - 4073
    Cited by:  Papers (13)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2156 KB) |  | HTML iconHTML  

    A metasurfing concept is demonstrated and applied in the design of Luneburg lens antennas. Using an array of size-varying circular patches on a dielectric substrate inside a parallel-plate waveguide (PPW) structure variable surface impedance is obtained, which realizes an equivalent refraction index as that of a Luneburg lens. The obtained lens has good bandwidth characteristics and significant fabrication advantages with respect to conventional dielectric lenses. Based on this PPW lens, an H-plane antenna has been designed and simulated. View full abstract»

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  • Design of High-Gain Lens Antenna by Gradient-Index Metamaterials Using Transformation Optics

    Publication Year: 2012 , Page(s): 4074 - 4081
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2053 KB) |  | HTML iconHTML  

    Transformation of space coordinates can be used as a convenient tool for producing a controlled electromagnetic field pattern. In this paper, using a conformal transformation, the design procedure of a lens antenna with high gain and low sidelobes is presented which can be realized by isotropic graded refractive index (GRIN) materials. Applying proper simplifying techniques, the designed lens can be made by non-resonant metamaterials or non-magnetic dielectrics having wide frequency band and low loss. A graded photonic crystal (GPC) operating in metamaterial regime is used for this purpose. By placing the lens in a horn antenna, a highly directive beam is achieved. It is also shown that by lateral displacement of the lens medium, the beam direction can be controlled to some extent. A multibeam antenna in which each beam can be controlled independently is also presented. Simulation results are used to justify the design approach. View full abstract»

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  • Dual-Polarized Sinuous Antennas on Extended Hemispherical Silicon Lenses

    Publication Year: 2012 , Page(s): 4082 - 4091
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2959 KB) |  | HTML iconHTML  

    This paper examines the performance of dual-linear sinuous antennas on silicon extended hemispherical silicon dielectric lenses. A theoretical impedance of 106 Ω is identified based on the analysis of an ideal self-complementary structure, and this result compares well with simulations and measurements. The radiation properties of a linearly polarized sinuous antenna are simulated using Method of Moments software coupled to a GO/PO code, and also agree well with measurements. The results indicate that the sinuous antenna is an excellent wideband planar feed for a silicon lens, with cross-polarization levels below -17 dB, and polarization variations of ±5° over two octaves in frequency. The application areas are millimeter-wave, wideband, dual-polarized radio-astronomy receivers. View full abstract»

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  • Independently Tunable Low-Profile Dual-Band High-Impedance Surface Antenna System for Applications in UHF Band

    Publication Year: 2012 , Page(s): 4092 - 4101
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1615 KB) |  | HTML iconHTML  

    An independently tunable low-profile dual-band high-impedance surface (HIS) antenna system is presented which employs a single layer cross bow-tie dual-band tunable HIS ground plane with a printed wideband monopole antenna designed to cover the UHF band. The unit cell of the proposed HIS ground plane is 19.71 mm by 19.71 mm with thickness of 1.74 mm. Simulations of the HIS ground plane have illustrated that either single or dual-band reconfigurable reflection phase resonances can be achieved between 0.95 GHz and 2.45 GHz by controlling C1 (4.55 pF~0.6 pF) and C2 (4.55 pF~0.6 pF) independently which represent the two groups of varactor diodes mounted on the surface elements of the HIS. Simulations with the wideband antenna 4 mm above the HIS ground plane illustrate an effective tunable operational bandwidth from 1.07 GHz to 2.75 GHz with a dual-band capability. Parametric studies indicate the radiation efficiency of the system increases as the antenna height is increased and the diode resistance is reduced. The radiation efficiency also increases with the frequency in general over the tunable frequency range and with the optimum parameters typical values from -4 dB to -2 dB can be achieved. The proposed HIS ground plane and the wideband antenna have been fabricated with Toshiba 1SV245 varactor diodes and it has shown an effective tunable bandwidth from 0.9 GHz to 2.8 GHz approximately with the dual band capability. View full abstract»

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  • 130-GHz On-Chip Meander Slot Antennas With Stacked Dielectric Resonators in Standard CMOS Technology

    Publication Year: 2012 , Page(s): 4102 - 4109
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1929 KB) |  | HTML iconHTML  

    This work discusses the design methodologies of 130-GHz high gain and high efficiency on-chip meander slot antennas in a standard CMOS technology. In the proposed structure, stacked dielectric resonators (DRs) are placed on the top of the on-chip feeding element to form series-fed antenna array for antenna gain and efficiency improvement. The integrated antenna with double stacked DRs achieved a measured gain of 4.7 dBi at 130 GHz with a bandwidth of 11%. The antenna size is 0.8 ×0.9 mm2 and the simulation results indicate a radiation efficiency of 43%. To the best of our knowledge, this is the first demonstration of an on-chip antenna gain and efficiency enhancement through stacked DRs. View full abstract»

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  • An Improved Design for a 1–18 GHz Double-Ridged Guide Horn Antenna

    Publication Year: 2012 , Page(s): 4110 - 4118
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (4180 KB) |  | HTML iconHTML  

    It is a well known fact that the traditional 1-18 GHz double ridge guide horn (DRGH) antenna suffers from pattern deterioration above 12 GHz. At these frequencies, instead of maintaining a single main lobe radiation pattern, the pattern splits up into four lobes. It was shown in the literature that higher order modes are causing the pattern breakup. A benchmark study is performed to establish the performance of typical current and historic 1-18 GHz DRGH antennas. The performance of the antennas are evaluated in terms of gain, VSWR and radiation patterns. An improved 1-18 GHz DRGH antenna is presented. The new design has better gain and VSWR performance without any pattern deterioration. It also consists of significantly fewer parts, reducing the possibility of performance deterioration due to gaps between parts. Two prototypes of the new design were manufactured and tested with excellent agreement between measured and simulated results. The aperture dimensions of the new design are identical to that of the traditional DRGH, making it the only 1-18 GHz DRGH without pattern breakup whose aperture dimensions comply with the requirements specified in MIL-STD-461F - 24.2 by 13.6 cm. View full abstract»

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  • A Bifocal Ellipsoidal Gregorian Reflector System for THz Imaging Applications

    Publication Year: 2012 , Page(s): 4119 - 4129
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2309 KB) |  | HTML iconHTML  

    Current terahertz imagers rely on reflector systems for the beam quality and imaging speed because the cross-range span that the system can cover is limited by the beam aberrations when the antenna scans. We present the design of a Bifocal reflector system that can rapidly scan a terahertz beam for standoff imaging applications while increasing the field of view of previous designs up to 50%. The design is based in a confocal Gregorian system where the nominal reflector surfaces are substituted by shaped surfaces to reduce the beam aberrations, while not increasing the manufacture cost of the reflector antenna. We also provide a set of useful design formulas for the design of this kind of reflector systems. The beam patterns obtained by the proposed designs are numerically calculated with the commercial software GRASP and compared with those obtained with previous approaches to the same problem, showing the better performance of the proposed solution. View full abstract»

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  • Design and Manufacturing of Robust Textile Antennas for Harsh Environments

    Publication Year: 2012 , Page(s): 4130 - 4140
    Cited by:  Papers (13)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1608 KB) |  | HTML iconHTML  

    Antennas made out of textile materials suffer from performance perturbing effects whose impact mainly depend on the mechanical properties of the fabrics. The soft and flexible nature of the fabrics is essential for user comfort in wearable systems, but makes the antenna performance sensitive to bending, stretching, compression, and the manufacturing process. Furthermore, water absorption into the woven textile structures can increase both the permittivity and the dielectric loss of the substrate materials. The potential performance reduction due to the material characteristics is addressed in this paper, and methods to improve performance robustness are introduced. Tests show that the use of a textile cover provides a rugged design which is insensitive to the effects of abrasion, saline water and varying climatic conditions. A dual frequency textile antenna is thoroughly tested and shown to be fully compliant with Iridium and GPS specifications. View full abstract»

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  • Embroidered Conductive Fibers on Polymer Composite for Conformal Antennas

    Publication Year: 2012 , Page(s): 4141 - 4147
    Cited by:  Papers (19)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1806 KB) |  | HTML iconHTML  

    We provide a novel class of conformal antennas based on embroidered conductive metal-polymer fibers (E-fiber) on polymer-ceramic composites. This new technology offers attractive mechanical and RF performance when compared to traditional flat and rigid circuits and antennas. The proposed E-fiber components are consisted of high strength and flexible polymer fiber cores and conductive metallic coatings. They were fabricated using automatic embroidery process, followed by assembly with polydimethylsiloxane and rare-earth titanate ceramic composites. Such composite substrates were tape-casted, and capable of providing tunable dielectric constant from 3 to 12 with a low tanδ <; 10-2 up to GHz frequencies. Basic RF prototypes, such as transmission lines (TL), patch antennas, and antenna arrays were fabricated for experimental evaluation. Measurement of the prototypes were conducted and compared to their copper counterparts. The RF characteristics of the E-fiber TLs exhibited an insertion loss of only 0.03 dB/cm higher than copper TLs up to 4 GHz . Also, the E-fiber patch antenna and antenna array exhibited 0.3 dB and 0.6 dB lower gains, respectively, than their copper counterparts. When applied onto a cylindrical surface, both the E-fiber patch antenna and antenna array only suffered 1 dB loss in realized gain, which is quite remarkable when compared with traditional antennas. View full abstract»

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  • Inkjet Printing of Novel Wideband and High Gain Antennas on Low-Cost Paper Substrate

    Publication Year: 2012 , Page(s): 4148 - 4156
    Cited by:  Papers (24)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1439 KB) |  | HTML iconHTML  

    A complete characterization of the inkjet printing process using metallic nanoparticle inks on a paper substrate for microwave frequencies up to 12.5 GHz as well as its application to low-cost, high gain and wideband antenna design are demonstrated in this work. Laser and heat sintering of metallic nanoparticles are compared on paper substrate for the first time which demonstrate immense cost and time benefits of laser sintering. The antennas fabricated using the characterized process include a Vivaldi for the UWB band which exhibits a significantly higher gain of up to 8 dBi as compared to the currently published inkjet printed antennas, and a novel slow-wave log periodic dipole array which employs a new miniaturization technique to show 20% width reduction. View full abstract»

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  • Tri-Band Dual-Polarization Shared-Aperture Microstrip Array for SAR Applications

    Publication Year: 2012 , Page(s): 4157 - 4165
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3323 KB) |  | HTML iconHTML  

    The design of a tri-band dual-polarization (TBDP) shared-aperture microstrip array antenna for synthetic aperture radar (SAR) applications is presented. It operates at L-, Sand X-bands with a frequency ratio of 1:2.8:8. This TBDP shared-aperture array is assembled by two L/S and L/X DBDP shared-aperture sub-arrays with one L-band dual-polarized sub-array. A prototype array has been fabricated and measured, which exhibits wide impedance bandwidth (VSWR ≤ 2) of 13.4%, 14.8%, and 16.8% in L-, S-, and X-bands, respectively. The measured array isolation is better than -27 dB in all three bands. The measured radiation patterns agree well with the simulation, confirming the cross-polarization level of below dB within the main lobe region, and the array scanning capability of ±27° in S- and X-bands. This array design approach can be further extended to shared-aperture arrays with more than three bands. View full abstract»

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  • Superstrate-Enhanced Ultrawideband Tightly Coupled Array With Resistive FSS

    Publication Year: 2012 , Page(s): 4166 - 4172
    Cited by:  Papers (13)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1776 KB) |  | HTML iconHTML  

    An efficient low-profile ultrawideband tightly coupled array employing a resistive frequency selective surface (FSS) and a superstrate is introduced. The FSS suppresses destructive ground plane interference, resulting in an increase in the array bandwidth by a factor greater than two. A superstrate is used to alleviate losses due to the resistive FSS. It is shown that a properly designed superstrate reduces losses by about 2.5 dB. The proposed array, which employs tightly coupled bowtie elements, achieves very low profile (0.055λlow) , 21:1 bandwidth, and radiation efficiency greater than 73% across the band. This paper presents the analysis and design of the array, particularly the FSS and superstrate. To validate the design, measurements of a prototype array are presented as well. View full abstract»

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  • Study on Two-Dimensional Sparse MIMO UWB Arrays for High Resolution Near-Field Imaging

    Publication Year: 2012 , Page(s): 4173 - 4182
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3154 KB) |  | HTML iconHTML  

    A novel generic topology for two-dimensional (2-D) sparse multiple-input-multiple-output (MIMO) ultrawideband (UWB) arrays is suggested. Based on the proposed topology, a 2-D MIMO UWB array for high-resolution short-range imaging is developed. The focusing properties of this array are studied both theoretically and experimentally and are shown to be superior to those of arrays with a similar number of antennas and based on known topologies such as Mills Cross, rectangular, and spiral configurations. Decisive impact of a large operational bandwidth and short focusing distance on MIMO array performance is shown. Imaging capabilities of the proposed array are experimentally demonstrated for distributed targets. View full abstract»

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  • Single Layer Reflectarray With Circular Rings and Open-Circuited Stubs for Wideband Operation

    Publication Year: 2012 , Page(s): 4183 - 4189
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1599 KB) |  | HTML iconHTML  

    The design of a single-layer reflectarray, which employs a new phasing element in the form of a fixed-size circular ring and a variable-length open-circuited stub, is presented. The array is developed on a thin substrate supported by a thick foam material. Investigations are performed to obtain a linear reflection phase as a function of the stub's length when the element operates in a unit cell. This goal is achieved by a suitable choice of the ring's radius and width and the stub's width. In order to validate the simulated element's reflection phase behavior, a waveguide simulator is manufactured to perform experimental tests. The phasing element offering best linear phase characteristics is used to design an -band offset fed 13×13 element reflectarray pointing at 20° from the broadside direction. Full-wave simulations performed using CST Microwave Studio show desired radiation characteristics of the designed array antenna. The simulated performance is confirmed by experimental tests performed on the fabricated reflectarray prototype showing a 17.8% 3-dB gain drop bandwidth. View full abstract»

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  • Characterization of a Reflectarray Gathered Element With Electronic Control Using Ohmic RF MEMS and Patches Aperture-Coupled to a Delay Line

    Publication Year: 2012 , Page(s): 4190 - 4201
    Cited by:  Papers (9)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2402 KB) |  | HTML iconHTML  

    A reflectarray element with electronic phase control implemented by ohmic MEMS switches is characterized and validated in the X-band. The proposed element is based on two patches aperture-coupled to a microstrip network with a common delay line, forming a sub-array, in order to reduce both cost and manufacturing complexity in large reflectarrays. The electrical length of the line can be modified through the inclusion of a series switch between different segments of the microstrip line. The ohmic electrostatic switch has been designed for RF applications and manufactured on a coplanar line. The transition between the coplanar line of the MEMS and the microstrip delay line has been implemented using gold wires which have been bonded to the printed pads. This connection leads to a high impedance line. The MEMS switches have been characterized using reflection and transmission measurements on microstrip lines for deducing an equivalent circuit, which has been used in the validation of the gathered element with electronic phase control measured using waveguide simulator. The same approach has been applied to evaluate a 2-bit reflectarray element. View full abstract»

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  • Reflectarray Design at Infrared Frequencies: Effects and Models of Material Loss

    Publication Year: 2012 , Page(s): 4202 - 4209
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1584 KB) |  | HTML iconHTML  

    Reflectarray designs at infrared (IR) frequencies are investigated in this paper. At the short-wavelength region, material loss becomes an important consideration in reflectarray designs. Based on the measured properties of conductors and dielectrics at infrared frequency, this paper investigates the loss effects on the reflection magnitude and phase of reflectarray elements. It is revealed that when the material loss exceeds a certain limit, the element reflection phase will vary within a narrow phase range instead of a full 360° phase range. An equivalent circuit model is used to understand this phenomenon. Based on the investigation, alternative design methods for infrared reflectarrays are suggested to lower the loss effect. The low loss reflectarrays have great potential for infrared and visible range applications, such as a low profile planar concentrator for solar energy systems. View full abstract»

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  • Non-Orthogonal Grids in Two-Dimensional Transmission-Line Metamaterials

    Publication Year: 2012 , Page(s): 4210 - 4218
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2078 KB) |  | HTML iconHTML  

    Characteristics of two-dimensional metamaterials based on non-orthogonal grids of transmission lines are investigated. From periodic analysis on a unit cell, the dispersion function is derived and compared with the orthogonal grid case. Isomorphism between Kirchhoff's circuital laws and two-dimensional Maxwell's equations is utilized to characterize the effective medium parameters. It is shown that a non-orthogonal grid structure is effective in realizing two-dimensional full-tensor anisotropic medium parameters in a simple geometrical configuration. For verification, a design example is provided where a probe current radiates near a planar interface between two anisotropic media and the results are compared with the analytical solution. View full abstract»

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  • Modeling of Spatially-Dispersive Wire Media: Transport Representation, Comparison With Natural Materials, and Additional Boundary Conditions

    Publication Year: 2012 , Page(s): 4219 - 4232
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3459 KB) |  | HTML iconHTML  

    Natural and artificial wire materials exhibiting spatial dispersion are considered using a transport (drift-diffusion) model. The connection between drift-diffusion and electron transport in natural materials is highlighted, and then applied to various forms of wire media, leading to the definition of effective conductivity and diffusion parameters that characterize the material. It is shown that the effective material parameters lead to a Debye length that provides a quantitative measure of the strength of spatial dispersion for wire mediums. Further, it is shown that Pekar's additional boundary condition applies in many instances to natural materials as well as artificial wire media, and can be derived from elementary electromagnetics. View full abstract»

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  • A True Domain Decomposition Procedure Based on Method of Moments to Handle Electrically Large Bodies

    Publication Year: 2012 , Page(s): 4233 - 4238
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1020 KB) |  | HTML iconHTML  

    A true domain decomposition method to obtain numerical solution involving electrically large bodies using the method of moments (MOM) formulation is the subject matter of the present work. The electrically large body is initially divided into smaller sub-structures. By defining a set of new basis functions adaptively, utilizing the primary basis functions, a solution scheme is developed which completely eliminates the interaction of one substructure with the rest of the body. This procedure enables to solve each substructure independently and involves no iterative solution as a final step. The present method is conceptually simple and applicable to any MOM solution. Further, the method can easily handle multiple right-hand side vectors much the same way as the conventional MOM solution. A few representative numerical examples are presented to illustrate the applicability of the new method. View full abstract»

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IEEE Transactions on Antennas and Propagation includes theoretical and experimental advances in antennas.

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Editor-in-Chief                                                 Kwok W. Leung