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Antennas and Propagation, IEEE Transactions on

Issue 7 • Date July 2012

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  • Table of contents

    Publication Year: 2012 , Page(s): C1 - 3082
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  • IEEE Transactions on Antennas and Propagation publication information

    Publication Year: 2012 , Page(s): C2
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  • Investigations on a Novel Folded Ring Resonator Antenna With Multiband Characteristics

    Publication Year: 2012 , Page(s): 3083 - 3090
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2102 KB) |  | HTML iconHTML  

    A novel loop antenna based on the volumetric folded ring resonator (FRR) structure is proposed. It is shown that the FRR antenna can be represented by an equivalent circuit model for approximate analysis with sufficient accuracy. Two practical implementations are presented: The first version is a single FRR antenna embedded in a dielectric substrate and excited by a 50 coaxial feed line. Parametric studies of the structural parameters are presented showing three resonances that can be impedance matched achieving positive gain. In the second implementation, the FRR is embedded in a slotted ground plane for improved matching and radiation performance. Two bands, one at 3.6 GHz and another between 4.75 GHz and 5.8 GHz, are matched to better than S11 = -10 dB and maintain a constant 2.5 dBi gain with >; 90% radiation efficiency. The simulated reflection coefficient and gain radiation patterns agree well with measurements. View full abstract»

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  • Planar Broadband Arc-Shaped Monopole Antenna for UWB System

    Publication Year: 2012 , Page(s): 3091 - 3095
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    A novel broadband design of planar arc-shaped monopole antenna with a rectangular parasitic patch for UWB system is proposed. With the use of rectangular parasitic patch, multi resonant modes are excited to meet the specifications of UWB system. Moreover, the obtained impedance bandwidth across the operating band can reach about 10.25 GHz. The measured peak gains and radiation efficiencies are about 1.2-5.3 dBi and 85-91% across the operating band, respectively, with nearly omni-directional pattern in the XY-plane. View full abstract»

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  • Small Patch Antennas Incorporated With a Substrate Integrated Irregular Ground

    Publication Year: 2012 , Page(s): 3096 - 3103
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1327 KB) |  | HTML iconHTML  

    This paper presents a novel method for size reduction of patch antennas by introducing an irregular ground structure to provide capacitive and inductive loading to the patch. Each of the four corners of the square patch is assigned with a pair of metallic walls. These special metallic walls located underneath the patch are constructed and integrated within the microwave substrate by connected vias. The vertical portion of the walls introduces the inductance whereas the separation between the two parallel walls creates the capacitance. Additional capacitances are also created between the flat strips connecting the vias and the radiating patch. No modifications are made to the square patch. With the presence of the substrate integrated irregular ground (SIIG) structure, the antenna finds a significant size reduction by the capacitive and inductive loading effect. For the proposed linearly-polarized antenna operating at 2.635 GHz, we achieve a total patch area reduction of 75.6% experimentally when compared with a half-wavelength patch antenna loaded with the same substrate. Furthermore, by using two sets of connecting strips with different lengths, two orthogonal modes are excited for circular polarization and similar size reduction effect is achieved. View full abstract»

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  • Effective Analysis of a Waveguide Longitudinal Slot With Cavity

    Publication Year: 2012 , Page(s): 3104 - 3110
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (997 KB) |  | HTML iconHTML  

    We propose an effective and accurate analysis technique based on the method of moments (MoM) for the characterization of a longitudinal slot with a short truncated waveguide above it. This antenna has been used in the recent literature as the radiating element of large waveguide arrays. We focus our attention on some features and applications of this configuration which have not been taken into account in previous works. Then, we discuss the need for a tailored, effective and accurate analysis technique linking the radiating properties of the proposed antenna to its circuital properties according to Elliott's model. This task is easy by using the MoM with entire domain sinusoidal basis functions. The results of our procedure are compared with those of Ansoft HFSS against the computational time, showing a significant improvement. View full abstract»

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  • Miniaturized and Reconfigurable CPW Square-Ring Slot Antenna Loaded With Ferroelectric BST Thin Film Varactors

    Publication Year: 2012 , Page(s): 3111 - 3119
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1514 KB) |  | HTML iconHTML  

    A novel miniaturized and reconfigurable coplanar waveguide (CPW) square-ring slot antenna is presented in this paper. The miniaturization is achieved via a hybrid approach including ferroelectric varactor loadings, high dielectric constant materials, and tuning stub for impedance matching. For the first time, nine shunt ferroelectric (FE) BST (Ba(1-x)SrxTiO3) thin film varactors are integrated with the CPW antenna structure achieving both antenna miniaturization and reconfiguration at the same time. The size of the miniaturized antenna is reduced to 0.067λ0 0.067λ0 without ground, and 0.1λ0 0.1λ0 with ground. The resonant frequency of the miniaturized antenna can be reconfigured from 5.3 GHz to 5.8 GHz by applying a DC voltage. Measured E-plane and H-plane co-polarized patterns are presented. View full abstract»

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  • Q Bounds for Arbitrary Small Antennas: A Circuit Approach

    Publication Year: 2012 , Page(s): 3120 - 3128
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2079 KB) |  | HTML iconHTML  

    Circuit models for the lowest-order modes radiating from within an arbitrarily-shaped envelope have been developed based on the exact circuits for spherical modes and the radar scattering from a conductor of the arbitrary shape. These circuits predict lower bounds on the Q of small antennas with any combination of coupling between modes. Circuit parameters are tabulated for a range of shapes, and the procedure for computing parameters for other shapes is explained. The bounds on a small circularly-polarized cylindrical antenna illustrate an application. Predictions for scattering by the arbitrary envelope filled with a high μ or ε material serve to validate the procedure. View full abstract»

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  • 60 GHz Plated Through Hole Printed Magneto-Electric Dipole Antenna

    Publication Year: 2012 , Page(s): 3129 - 3136
    Cited by:  Papers (18)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1330 KB) |  | HTML iconHTML  

    A wideband unidirectional antenna, which is composed of a planar electric dipole and a magnetic dipole formed by a vertically-oriented shorted patch antenna, is presented for millimeter wave applications. The antenna is realized by a plated through hole printed technique with the use of a microwave substrate and is excited by a T-shaped coupled strip feed. An impedance bandwidth of 33% (S11 ≤-15 dB) from 50 to 70 GHz is achieved. Stable radiation patterns with low cross polarizations and a stable antenna gain of ~7.5 dBi are achieved across the entire operating bandwidth. This single antenna element yields advantages of wideband, good directional radiation pattern and low fabrication cost. View full abstract»

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  • Tolerance Analysis of ALMA Band 10 Corrugated Horns and Optics

    Publication Year: 2012 , Page(s): 3137 - 3145
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1736 KB) |  | HTML iconHTML  

    Atacama Large Millimeter/sub-millimeter Array (ALMA) band 10 corrugated horns and optics (787-950 GHz) have been analyzed considering manufacturing and assembly tolerances. The results of thousands of Method-of-Moments and Physical-Optics simulations have been used to determine the impact of these tolerances on final electrical performances. Results on cross-polarization level and focus position, among others, are of special interest. This analysis has been compared with real measurements of ALMA band 10 production components. Results of measurements performed with a high number of corrugated horns match the statistical results fairly well. This study is important to assess the repeatability of results for different fabrications of the same component at THz frequencies. View full abstract»

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  • Design of Implanted RFID Tags for Passive Sensing of Human Body: The STENTag

    Publication Year: 2012 , Page(s): 3146 - 3154
    Cited by:  Papers (9)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1971 KB) |  | HTML iconHTML  

    Numerical processing of passive UHF-RFID tags' response may provide physical insight about the hosting object or about the nearby environment. This idea is here extended to implanted antennas with the purpose to sense the evolution of some human physiological and pathological process involving a local change of effective permittivity inside the body. The goal is to understand how master the design of this class of devices taking into account both communication and sensing capabilities. An ad hoc design methodology is here presented and discussed by means of a realistic medical case concerning the modification of an endo-vascular device to achieve a STENTag able to sense the state of the vessel wherein it has been implanted. View full abstract»

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  • Generating Evanescent Bessel Beams Using Near-Field Plates

    Publication Year: 2012 , Page(s): 3155 - 3164
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1939 KB) |  | HTML iconHTML  

    We present a near-field plate that can generate an evanescent Bessel beam. The metallic plate consists of nonperiodic concentric corrugations that surround a coaxially fed aperture. The design procedure for such a device is outlined. The designed plate is simulated using a full-wave electromagnetic solver and is shown to produce an evanescent Bessel beam, thereby verifying its design and operation. The performance of the near-field plate is contrasted against a coaxial probe and a near-field plate designed to produce an Airy focal pattern with the same beamwidth. Such a device, capable of producing evanescent Bessel beams, will find applications in near-field probing/imaging systems, data storage, and biomedical devices. View full abstract»

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  • Periodic Leaky-Wave Antenna Array With Horizontally Polarized Omnidirectional Pattern

    Publication Year: 2012 , Page(s): 3165 - 3173
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1905 KB) |  | HTML iconHTML  

    A novel periodic leaky-wave antenna for broadside radiation with horizontally polarized omnidirectional pattern is proposed, designed and demonstrated experimentally. The objective is to achieve a horizontally polarized omnidirectional antenna array with highly directive beam. The proposed structure is based on combining the rotating electric field method and a leaky-wave antenna design. By properly designing a unit cell with a pair of crossed dipoles spaced at a distance approximately equal to λg/4 at the center frequency, not only omnidirectional radiation pattern with horizontal polarization is obtained by crossed dipoles fed in phase quadrature, but also the open-stopband effect exhibited at broadside scan is significantly reduced. The analysis and design of this structure are performed on the basis of a simple equivalent network model. A finite structure formed by 16-unit cell (32-element) for broadside beam is developed at the 2.4 GHz band, which offers a horizontally polarized omnidirectional radiation pattern with enhanced gain of 9.9-10.6 dBi and measured radiation efficiency of 90% for the covering bands. View full abstract»

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  • Position Mutated Hierarchical Particle Swarm Optimization and its Application in Synthesis of Unequally Spaced Antenna Arrays

    Publication Year: 2012 , Page(s): 3174 - 3181
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1702 KB) |  | HTML iconHTML  

    A family of position mutated hierarchical particle swarm optimization algorithms with time varying acceleration coefficients (viz. PM_nHPSO-TVAC, n = 1, 2, 3, 4) is introduced in this paper. The proposed position mutation schemes help the swarm to get out of local optima traps and the hierarchical nature of the swarm prevents premature convergence. One distinct advantage of the proposed algorithms over the existing mutated PSO algorithms is that PM_nHPSO-TVAC do not involve any controlling parameter. Performance of the proposed algorithms is evaluated on standard benchmark functions. Comparative study shows that PM_4HPSO-TVAC performs better than the other PM_n HPSO-TVAC, HPSO-TVAC, comprehensive learning PSO (CLPSO), adaptive-CLPSO (A-CLSPO), PSO with time-varying inertia weight (PSO-TVIW), and constriction factor PSO (CFPSO) for the benchmark functions considered. We apply the proposed algorithm to the synthesis of uniformly excited, unequally dpaced linear array to minimize sidelobe level (SLL) and to control first-null-beamwidth (FNBW) and null locations. Further, we apply the proposed algorithm to the synthesis of unequally spaced sparse planar array to minimize SLL. View full abstract»

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  • Synthesis, Simulation and Experiment of Unequally Spaced Resonant Slotted-Waveguide Antenna Arrays Based on the Infinite Wavelength Propagation Property of Composite Right/Left-Handed Waveguide

    Publication Year: 2012 , Page(s): 3182 - 3194
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2721 KB) |  | HTML iconHTML  

    Synthesis, simulation and experiment of unequally spaced resonant slotted-waveguide antenna arrays based on the infinite wavelength propagation property of composite right/left-handed (CRLH) waveguide has been demonstrated in this paper. Both the slot element spacing and excitation amplitude of the antenna array can be adjusted to tailor the radiation pattern. A specially designed shorted CRLH waveguide, as the feed structure of the antenna array, is to work at the infinite wavelength propagation frequency. This ensures that all unequally spaced slot elements along the shorted CRLH waveguide wall can be excited either inphase or antiphase. Four different unequally spaced resonant slotted-waveguide antenna arrays are designed to form pencil, flat-topped and difference beam patterns. Through the synthesis, simulation and experiment, it proves that the proposed arrays are able to exhibit better radiation performances than conventional resonant slotted-waveguide antenna arrays. View full abstract»

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  • Constrained Pareto Optimization of Wide Band and Steerable Concentric Ring Arrays

    Publication Year: 2012 , Page(s): 3195 - 3204
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1795 KB) |  | HTML iconHTML  

    A multi-objective evolutionary algorithm that explicitly introduces the management of a single or multiple constraints on the solutions of an electromagnetic problem is presented in this paper. The proposed strategy is based upon a modified genetic algorithm which evaluates the strength of a solution by considering both the match to the desired performance (objectives) as well as the satisfaction of specific requirements imposed to the design (constraints). The key issue is represented by the adaptive constraints management and its influence on the selective pressure of the genetic algorithm. The procedure is applied to the optimization of concentric ring arrays. Several design examples of steerable and wideband arrays are provided to prove the flexibility and reliability of the approach. A particular emphasis is given to the changes in array performance when the same objectives are requested but different kinds of constraints are forced. View full abstract»

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  • ANN Characterization of Multi-Layer Reflectarray Elements for Contoured-Beam Space Antennas in the Ku-Band

    Publication Year: 2012 , Page(s): 3205 - 3214
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3016 KB) |  | HTML iconHTML  

    The analysis of a 1.2-meter, contour-shaped reflectarray antenna through the use of Artificial Neuronal Networks (ANNs) is carried out in this paper. The analysis is a two-step procedure: reflectarray element modeling and pattern synthesis. In the first step, artificial neural networks are found to reproduce both the amplitude and the phase of the complex reflection coefficient of the three-layered reflectarray element. For this task, up to 9 free input parameters are considered: six geometrical parameters, the incident angle in terms of azimuth, θ, and elevation, φ, and the frequency. Because of this large number of free parameters, a new artificial neural network training methodology has been developed regarding both the training set and the training process itself. In the second step, extensive full wave electromagnetic computation is replaced by trained artificial neural networks to calculate the electric field on the planar structure and the radiation pattern. A good agreement is obtained compared to an analogous analysis carried out by Method of Moments. Thanks to this methodology, the speed up factor in terms of time is in the order of 7×102, which represents a significant improvement in Computer Aided Design (CAD) of reflectarray antennas. View full abstract»

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  • A New Approach Combining Surrounded-Element and Compression Methods for Analyzing Reconfigurable Reflectarray Antennas

    Publication Year: 2012 , Page(s): 3215 - 3221
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2411 KB) |  | HTML iconHTML  

    An efficient technique to provide fast and accurate analysis of large-scale and complex reconfigurable reflectarray antennas is presented and validated. The method combines the surrounded cell approach and the compression technique to analyze the global array. It takes into account the mutual coupling effects and the numerical complexity is reduced. Only a minor electromagnetic simulation and a fast post-processing are required. View full abstract»

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  • A Novel Amplitude-Only Measurement Method to Determine Element Fields in Phased Arrays

    Publication Year: 2012 , Page(s): 3222 - 3230
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2248 KB) |  | HTML iconHTML  

    A novel amplitude-only measurement method is proposed for phased array calibrations. The proposed method can determine a complex element field at every phase shift of a digital phase shifter in phased arrays. The method can be realized using higher order Fourier coefficients of one array-power response measured with the conventional rotating element electric field vector (REV) method. Simulations and experiments were carried out, including transmission errors from the phase shifters, which validated the proposed method. More accurate calibration and beam forming can be achieved by using the precise element fields at all phase shifts determined by the proposed method. View full abstract»

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  • Minkowskian Isotropic Media and the Perfect Electromagnetic Conductor

    Publication Year: 2012 , Page(s): 3231 - 3245
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3667 KB) |  | HTML iconHTML  

    The perfect electromagnetic conductor (PEMC) was introduced as an observer-independent “axion medium” that generalizes the concepts of perfect electric conductor (PEC) and perfect magnetic conductor (PMC). Following the original boundary definition, its 3-D medium definition corresponds to a 4-D representation that is, actually, observer-dependent (i.e., it is not isotropic for the whole class of inertial observers), leading to a nonunique characterization of the electromagnetic field inside. This characterization of the PEMC, then, violates the boundary conditions-unless some extraneous waves, called “metafields,” are surgically extracted from the final solution. In this paper, using spacetime algebra, we define the PEMC as the unique limit of the most general class of isotropic media in Minkowskian spacetime, which we call Minkowskian isotropic media (MIM). An MIM is actually a “dilaton-axion medium.” Its isotropy is a Lorentz invariant characterization: It is an observer-independent property, contrary to isotropy in 3-D Gibbsian characterization. Hence, a more natural definition of a PEMC is herein presented: It leads to a unique electromagnetic field in its interior; it corresponds, though, to the same original boundary definition. This new approach is applied to the analysis of an air-MIM interface that, as a particular case, reduces to an air-PEMC interface. View full abstract»

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  • A 3-D Global Earth-Ionosphere FDTD Model Including an Anisotropic Magnetized Plasma Ionosphere

    Publication Year: 2012 , Page(s): 3246 - 3256
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2396 KB) |  | HTML iconHTML  

    A 3-D global Earth-ionosphere finite-difference time-domain (FDTD) model is introduced that includes for the first time an anisotropic magnetized cold plasma ionosphere. All previous global FDTD Earth-ionosphere models to date have employed an isotropic conductivity profile. To generate the new model, a previously validated and published 3-D Cartesian magnetized cold plasma algorithm is adapted to the global latitude-longitude FDTD mesh that involves trapezoidal cells, merging of cells in the Polar regions, and triangular cells at the Poles. The global geomagnetic field, ionospheric particle densities and collision frequencies, as well as the Earth's topographic and bathymetric data are all mapped onto the global space grid. After a local high-resolution validation that demonstrates correct calculations of electromagnetic propagation in magnetized plasma, another numerical study is performed to validate the model on a global scale. This new model opens doors to a wide variety of advanced modeling for higher frequency and higher altitude electromagnetic phenomena and represents a paradigm shift from the commonly used ray-tracing codes. It also provides the opportunity to couple FDTD Earth-ionosphere models to other geophysical models, such as the Naval Research Lab's SAMI3, to yield a multiphysics simulator. View full abstract»

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  • Integral-Based Exponential Time Differencing Algorithms for General Dispersive Media and the CFS-PML

    Publication Year: 2012 , Page(s): 3257 - 3264
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1659 KB) |  | HTML iconHTML  

    Two efficient integral-based exponential time differencing (ETD) algorithms for general dispersive media in the finite-difference time domain (FDTD) are introduced. The first employs a linear approximation for the field over an integral time step in the integrand (denoted Algorithm I), and the second employs a Taylor series for approximating the field over the integral time step (denoted Algorithm II). Compared with the auxiliary differential equation (ADE) method and the piecewise linear recursive convolution (PLRC) method, the proposed algorithms have the same second-order accuracy but can lead to a substantial saving in both the memory space and CPU time consumption. To complete the scheme for the open region problems, a novel integral-based ETD implementation of the complex frequency shifted perfectly matched layer (CFS-PML) is proposed. Compared with the well-known recursive convolution implementation of the CFS-PML (CPML), this new implementation can lead to a substantial saving in the CPU time and a significant improvement of around 20 dB in the absorbing performance. And through the integral-based ETD algorithm, a much simpler interpretation of the CPML is presented. View full abstract»

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  • Analysis of Dispersive Effects and Enhanced Medium Penetrability in Wide-Band Pulse Propagation Through Sparse Discrete Media

    Publication Year: 2012 , Page(s): 3265 - 3277
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2675 KB) |  | HTML iconHTML  

    Evolution of an oscillatory wide-band pulse in a sparse medium composed of randomly distributed, uncorrelated, discrete scatterers (such as atmospheric clouds, dust, or other aerosols) is studied. The frequency-dependent (dispersive) losses are evaluated by taking into account energy absorption in the medium constituents as well as scattering itself. A reduced, algebraic attenuation of the pulse energy is observed, provided the pulse contains a significant frequency content in the region of strongly varying medium dispersive properties. These frequencies can be provided by pulse carrier frequency selection, short rise and fall times of the pulse, or pulse chirping. It is shown that different types of algebraic attenuation, over the range of penetration depth corresponding to several orders of mean-free path, can be present depending on the inter-relations between characteristic frequencies of the pulse spectrum and the medium dispersive properties. A simple analytical model is constructed that captures relevant features of the propagating pulse energy decay, as well as ranges of penetration depths, and hence may serve as a useful tool in designing and analyzing various scenarios of wide-band pulse propagation in dispersive media in the context of, e.g., signal transmission, imaging, or target detection. View full abstract»

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  • Transmission Through an Arbitrary Aperture in a 3-D Conducting Surface Enclosing Chiral Material

    Publication Year: 2012 , Page(s): 3278 - 3284
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1737 KB) |  | HTML iconHTML  

    The problem of electromagnetic transmission through an arbitrarily shaped aperture in an arbitrarily shaped 3-D conducting surface enclosing homogeneous chiral material is investigated. To solve the problem numerically, the surface equivalence principle and the method of moments are used. The validity of the procedure has been checked by comparing the numerical results to other available solutions whenever possible. Numerical results for the physical electric current on the surface of the obstacle, the internal field, and the bistatic radar cross section are presented for the examples of a sphere and a finite cylinder with circular apertures. These results are computed for various electrical sizes, permittivity values, chirality values, and aperture sizes. View full abstract»

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  • A Novel Meshless Scheme for Solving Surface Integral Equations With Flat Integral Domains

    Publication Year: 2012 , Page(s): 3285 - 3293
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1333 KB) |  | HTML iconHTML  

    Numerical solutions for electromagnetic (EM) integral equations rely on the discretization of integral domains and the use of meshes for geometric description. Meshing geometries is very tedious, especially for complicated structures with many details (tiny parts) and geometric discontinuities (corners or edges), and remeshing could be required in many scenarios. To reduce the costs of generating quality meshes, meshless or mesh-free methods were developed and they have been extensively studied in mechanical engineering though there are less obvious interests in EM community. The meshless methods employ discrete nodes to replace meshes in the description of geometries but the background meshes for integrations are still needed traditionally. In this work, we first address the traditional meshless scheme for solving EM integral equations based on the moving least square (MLS) approximation for unknown currents and the use of background meshes for integrations, and then develop a novel meshless scheme by applying the Green's lemma to the EM surface integral equations with flat domains. The novel scheme transforms a surface integral over a flat domain into a line integral along its boundaries when excluding a singular patch in the domain. Since only the domain boundaries are discretized and no background meshes are needed, the scheme is truly meshless. Numerical examples for EM scattering by flat-surface objects are presented to demonstrate the effectiveness of the novel scheme. 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