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Antennas and Propagation, IEEE Transactions on

Issue 9 • Date Sept. 2009

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Displaying Results 1 - 25 of 47
  • Table of contents

    Publication Year: 2009 , Page(s): C1 - 2517
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  • IEEE Transactions on Antennas and Propagation publication information

    Publication Year: 2009 , Page(s): C2
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  • Phase-Corrected Near-Field Measurements of the TELIS Telescope at 637 GHz

    Publication Year: 2009 , Page(s): 2518 - 2525
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1264 KB) |  | HTML iconHTML  

    Results are presented for the telescope optics verification of the TELIS instrument which is developed and constructed at the Deutsches Zentrum fU??r Luft- und Raumfahrt (DLR), Germany. TELIS is a balloon-borne limb-sounding radiometer which measures pressure-broadened emission lines of various species of the earth's atmosphere. Due to the strong brightness gradient in the limb-viewing geometry the antenna beam of the instrument needs to be well-defined in order to ensure proper operation. Near-field measurements made at 637 GHz of the TELIS telescope were used to derive the far-field pattern. Error compensation included correction of the phase error of the near-field data due to cable flexing. The phase error due to cable flexing was measured using a technique based on heterodyne reception of the signal reflected at the end of the cable. The results are compared to an optics model based on physical optics. Discrepancies between measurements and the model are resolved by misaligning the mirrors in the optics model while minimizing the deviations from theory and experiment. View full abstract»

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  • Multiband Handset Antenna Combining a PIFA, Slots, and Ground Plane Modes

    Publication Year: 2009 , Page(s): 2526 - 2533
    Cited by:  Papers (56)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1481 KB) |  | HTML iconHTML  

    A multiband handset antenna combining a PIFA and multiple slots on a ground plane is presented. It is shown by means of simulations that the slots on the ground plane have a double function: to tune the ground plane resonance at low frequencies (f ?? 900 MHz) and to act as parasitic radiators at high frequencies (f ?? 1800 MHz). A prototype is designed and built featuring a behavior suitable for low frequencies (GSM850 and GSM900) and for high frequencies spanning from DCS1800 to Bluetooth, and including, for instance, PCS1900, UMTS2000, and other possible systems. Reflection coefficient, efficiency, and radiation patterns are measured and compared with a design without slots to prove the advantages of the slotted ground plane. The component effect is investigated to determine critical areas where the placement is not recommended. Besides, the effect of the slot of the ground plane on SAR is investigated, by discussing the effect of the ground plane and slot modes for two phone positions. The total antenna volume of the proposed design is 40 ?? 15 ?? 6 mm3. View full abstract»

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  • Compact PIFA for Mobile Terminals Supporting Multiple Cellular and Non-Cellular Standards

    Publication Year: 2009 , Page(s): 2534 - 2540
    Cited by:  Papers (29)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (969 KB) |  | HTML iconHTML  

    A novel multiband planar inverted-F antenna (PIFA) covering ten frequency bands has been proposed for personal wireless communications terminals. The design is based on the combination of various techniques that are used for designing multiband/broadband antennas. We used a shorted parasitic patch efficiently coupled to the driven patch, a quarter-wave resonator connected to the feed strip in parallel with the main patch, and four slits in the main radiator to excite various current modes in the antenna structure. The antenna is designed within a volume of 4.0 times 2.0 times 0.8 cm3 and it can be used to serve the following wireless communication systems: Global System for Mobile Communications (GSM-900), Digital Communications System (DCS), Personal Communication Service (PCS), Universal Mobile Telecommunications System (UMTS), WiBro at 2.35 GHz, Bluetooth, Satellite-Digital Multimedia Broadcasting (SDM-B) at 2.65 GHz, WiMAX at 3.5 GHz, and the two bands (5.15-5.35 GHz and 5.725-5.875 GHz) for the wireless Local Area Network (WLAN) standards. A prototype antenna was fabricated and tested for input reflection coefficient and radiation performances. The measured and simulated results have been presented and discussed. Important geometrical parameters determining the multiband performances of the antenna have been explained in the paper. View full abstract»

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  • Quarter-Wavelength Printed Loop Antenna With an Internal Printed Matching Circuit for GSM/ DCS/PCS/UMTS Operation in the Mobile Phone

    Publication Year: 2009 , Page(s): 2541 - 2547
    Cited by:  Papers (54)  |  Patents (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1149 KB) |  | HTML iconHTML  

    A small-size printed loop antenna with an internal printed matching circuit capable of GSM/DCS/PCS/UMTS operation in the mobile phone is proposed. The antenna comprises an 85-mm long folded loop strip and an internal printed matching circuit encircled therein and formed by a coupling strip and an inductive strip. The loop strip is excited by the coupling strip to generate a 0.25 lambda resonant mode at about 900 MHz for GSM operation. For the inductive strip, it effectively causes a wideband higher order mode at about 1900 MHz for DCS/PCS/UMTS operation. Further, the antenna shows a uniplanar structure and requires a very small printed area of 170 mm2 on the system circuit board of the mobile phone, making it easy to fabricate at low cost. Details of the proposed antenna and its radiation performances including the SAR (specific absorption rate) results are studied. View full abstract»

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  • Low-Q, Electrically Small, Efficient Near-Field Resonant Parasitic Antennas

    Publication Year: 2009 , Page(s): 2548 - 2563
    Cited by:  Papers (21)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2004 KB) |  | HTML iconHTML  

    Metamaterial-inspired electrically small Z, stub and canopy antennas are reported. They are near-field, resonant parasitic designs. Different Z and stub antenna configurations and the effect on their Q values are studied. Their behavior led to the canopy antenna design. At the size of ka ~ 0.046, the canopy antenna is an electric-based antenna with high overall efficiency (over 90%) and low Q-ratio value and whose input resistance is almost completely matched to a 50 Omega source. The resonant frequency, ~300 MHz, in the UHF band is selected for the designs. The canopy antenna is studied extensively to explore the lowest achievable Q values. Various coupling configurations, canopy shapes, and metal-air ratios are investigated. Circuit models are also introduced to explain the radiation mechanism. Numerical simulation results are analyzed and compared with previously derived Q value limits for electrically small antennas that are based on the standard circuit models of spherical wave multipoles. The Q value of the canopy antenna for the lowest order, single electric resonance is shown to reach a fundamental limit of approximately 1.75 times the Chu value. View full abstract»

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  • Compact Patch Antenna for Electromagnetic Interaction With Human Tissue at 434 MHz

    Publication Year: 2009 , Page(s): 2564 - 2571
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1588 KB) |  | HTML iconHTML  

    Single element loop, dipole and conventional square patch antennas have been used as hyperthermia applicators in the treatment of cancerous human cells at superficial depths inside the body. A smaller novel patch antenna in very close proximity to a phantom tissue model produces an enhanced specific absorption rate pattern without significant frequency detuning or impedance mismatch. The new patch increases its coupling aperture by supporting a combination of resonances that are also typical for loop, dipole and square patch antennas. For computation efficiency and clarity in the synthesized hyperthermia treatment conditions, simplified planar tri-layered tissue models interfaced with a water-bolus are used to study the permittivity loading on the antennas and the resultant specific absorption rates. View full abstract»

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  • On the Dispersive Nature of the Power Dissipated Into a Lossy Half-Space Close to a Radiating Source

    Publication Year: 2009 , Page(s): 2572 - 2582
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (623 KB) |  | HTML iconHTML  

    We study how the power dissipated into a lossy medium excited by a nearby antenna is affected by drifts in the electrical parameters of the lossy medium. The statistical distribution of the sensitivity of the dissipated power is determined by means of a spectral analysis of the transmission of electromagnetic energy from air into the lossy half-space. A clear link is drawn between the reactive content of the field excited by the source and the dispersiveness of the sensitivity. The case of a stratified structure is also addressed, by defining a modification factor representing the alteration of the transmissivity and of its sensitivity when a buffer layer is introduced. All of the results provided point out that, in general, the sensitivity of the total amount of power dissipated into the half-space cannot be predicted independently from a precise knowledge of the source characteristics, unless under a paraxial propagation approximation or in a far-field configuration. View full abstract»

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  • Monolithically Integrated Corporate-Fed Cavity-Backed Antennas

    Publication Year: 2009 , Page(s): 2583 - 2590
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1980 KB) |  | HTML iconHTML  

    A Ka-band monolithically integrated 4 ?? 1 corporate-fed cavity-backed patch antenna array is demonstrated in this paper. A single antenna element has four slits introduced to extend the bandwidth to about 8%. Its gain and radiation efficiency are 6.3 dBi and 97%, respectively. A rectangular ??-coaxial line based combining network is monolithically integrated with radiating elements in a slightly modified tile configuration. Specifically, to reduce the array footprint power dividers are aligned along the array axis. Combining network has height 1/2 that of the array and feed lines do not route through the antenna elements. Overall loss of the combining network is 0.5 dB at 30 GHz. Measured reflection coefficient bandwidth and maximum gain of the fabricated 4 ?? 1 corporate-fed array are 13.7% and 12.73 dBi, respectively. The array is designed and fabricated in a recently developed surface micromachining process known as PolyStrata. View full abstract»

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  • Dual-Band Compact DRA With Circular and Monopole-Like Linear Polarizations as a Concept for GPS and WLAN Applications

    Publication Year: 2009 , Page(s): 2591 - 2598
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1949 KB) |  | HTML iconHTML  

    The concept of achieving a dual-band antenna with two different radiation patterns using a single cylindrical dielectric resonator is presented. Both simulated and experimental measured results are conducted to prove the validity of the proposed concept. A broadside circularly-polarized pattern with 7% bandwidth and a vertically polarized omnidirectional pattern with 17.3% bandwidth are obtained, simultaneously. The minimum measured axial ratio is found to be 1.3 dB. The front-to-back ratio is measured to be 15 dB. A design suitable for both Global Positioning System and wireless local area network applications is proposed. View full abstract»

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  • A Single Polarized Triangular Grid Tapered-Slot Array Antenna

    Publication Year: 2009 , Page(s): 2599 - 2607
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1238 KB) |  | HTML iconHTML  

    A triangular grid single polarized tapered-slot array antenna for radar applications is studied. Compared with a rectangular grid an equilateral triangular grid allows a larger unit cell without any onset of grating lobes. Since single polarized tapered-slots in triangular grids support guided modes, which cause scan blindness, the increase in unit cell size is smaller than the optimal 15%. The design presented in the paper is capable of scan angles out to 60?? from broadside in the E and H planes. To improve the match over the radar band a local minimum in the active reflection coefficient is positioned at the most critical scan direction, resulting in a reflection coefficient that is less than -12 dB in the X-band. To reduce the radar cross section for the cross-polarization an absorbing layer is positioned above the ground plane, which affects some of the guided modes that lead to scan blindnesses. An experimental antenna with 16 ?? 16 elements was built, and it was found that the H-plane performance for large scan angles for the finite antenna deviates more than expected from the infinite array approximation. Otherwise both mutual coupling measurements and embedded element patterns agrees well with the numerical results. View full abstract»

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  • Geometric Design and Comparison of Multifaceted Antenna Arrays for Hemispherical Coverage

    Publication Year: 2009 , Page(s): 2608 - 2614
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (735 KB) |  | HTML iconHTML  

    We address the optimization of the geometric design of two classes of multifaceted antenna arrays, namely, pyramids and pyramidal frusta. The optimization involves choosing the face elevation and the number of arrays. The optimal face elevation minimizes the maximum scan angle encountered by the arrays, given a general hemispherical coverage requirement. Firstly, an approach is presented to compute the face elevation of the pyramidal frustum, based on equalizing the maximum scan angles. It is demonstrated that the equalization-based approach is not always optimal. Secondly, a new optimal approach based on minimax optimization is presented and used for both pyramids and pyramidal frusta, along with a comparison of the two approaches. Finally, the choice of the number of arrays is addressed using different cost functions including scan angles, scan losses, antenna dimensions, geometric directivity, and total number of antenna elements. Quantitative guidelines on how to choose among planar, pyramidal, and pyramidal frustum antenna systems are outlined. View full abstract»

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  • Pattern Synthesis of Conformal Array Antenna in the Presence of Platform Using Differential Evolution Algorithm

    Publication Year: 2009 , Page(s): 2615 - 2621
    Cited by:  Papers (17)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (709 KB) |  | HTML iconHTML  

    A synthesis method based on differential evolution algorithm is proposed for conformal antenna arrays in the presence of platform. With the desired phase weights determined by the scan angle and array geometry, the amplitude weights of elements are optimized by differential evolution algorithm to drive down the side-lobes. Both the effect of platform on radiation pattern of conformal array and the mutual coupling between the elements are taken into account by calculating the antenna array and platform simultaneously using the method of moment. Application of adaptive integral method reduces the storage and computation time needed by the method of moments. View full abstract»

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  • Interleaved Ultrawideband Antenna Arrays Based on Optimized Polyfractal Tree Structures

    Publication Year: 2009 , Page(s): 2622 - 2632
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2143 KB) |  | HTML iconHTML  

    There is considerable interest in interleaving multiple phased array antennas into a single common aperture system. Current phased array antenna technology is limited to narrowband operation, leading to the appearance of grating lobes and strong mutual coupling effects when they are incorporated into the design of a common aperture system. To overcome this obstacle, a new class of arrays, called polyfractal arrays, has been introduced that possess natural wideband properties well suited for large-scale genetic algorithm optimizations. These arrays also possess recursive beamforming properties and an autopolyploidy-based chromosome expansion that can dramatically accelerate the convergence of a genetic algorithm. In addition, a robust Pareto optimization can be applied to reduce the peak sidelobe levels at several frequencies throughout the intended operating band, leading to ultrawideband antenna array designs. Because of their lack of grating lobes, these polyfractal arrays are ideal building blocks for interleaved antenna array systems. This paper develops these concepts, first creating ultrawideband array designs based on polyfractal geometries and then interleaving these designs into a common aperture system. Several examples of interleaved systems are discussed, with one two-array system possessing a peak sidelobe level of nearly -18 dB with no grating lobes over a 20:1 bandwidth with either of the component array mainbeams steered independently up to 60?? from broadside. View full abstract»

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  • Directional Modulation Technique for Phased Arrays

    Publication Year: 2009 , Page(s): 2633 - 2640
    Cited by:  Papers (29)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (399 KB) |  | HTML iconHTML  

    A directional modulation (DM) technique using a phased array to produce the modulation is presented. By phase shifting each element correctly, the desired amplitude and phase of each symbol in a digital modulation scheme can be produced in a given direction with data rates determined by the switching speed of the phase shifters. Because this signal is direction-dependent, the technique offers security, as the signal can be purposely distorted in other directions. DM also enables an array to send independent data in multiple directions. When using an array with driven elements, the phase shifts can be determined from simple calculations rather than time-consuming simulations or measurements. Mathematical analysis and experimental results are presented. View full abstract»

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  • Use of Asymptotic Waveform Evaluation Technique in the Analysis of Multilayer Structures With Doubly Periodic Dielectric Gratings

    Publication Year: 2009 , Page(s): 2641 - 2649
    Cited by:  Papers (9)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (440 KB) |  | HTML iconHTML  

    The reflection and dispersion characteristics of multilayer structures that involve periodically implanted material blocks are obtained by using the MoM solution of the volume integral equation. The asymptotic waveform evaluation (AWE) technique is utilized to obtain a Pade approximation of the solution in terms of a parameter such as frequency or incident angle. The use of AWE technique enables a fast sweep with respect to the approximation parameter. Moreover, a robust method for extracting the dispersion characteristics of periodic structures via Pade approximation is proposed. The AWE procedure requires the calculation of high order derivatives of the complicated kernel function that consists of Green's functions for stratified medium. These derivatives are calculated by employing the automatic differentiation theory. The reflection coefficient, propagation constant and band diagram of the structure are obtained both via point-by-point simulations and through the use of AWE technique. It is observed that AWE technique increases the computational efficiency without losing accuracy. View full abstract»

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  • Contamination of the Accuracy of the Combined-Field Integral Equation With the Discretization Error of the Magnetic-Field Integral Equation

    Publication Year: 2009 , Page(s): 2650 - 2657
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1137 KB) |  | HTML iconHTML  

    We investigate the accuracy of the combined-field integral equation (CFIE) discretized with the Rao-Wilton-Glisson (RWG) basis functions for the solution of scattering and radiation problems involving three-dimensional conducting objects. Such a low-order discretization with the RWG functions renders the two components of CFIE, i.e., the electric-field integral equation (EFIE) and the magnetic-field integral equation (MFIE), incompatible, mainly because of the excessive discretization error of MFIE. Solutions obtained with CFIE are contaminated with the MFIE inaccuracy, and CFIE is also incompatible with EFIE and MFIE. We show that, in an iterative solution, the minimization of the residual error for CFIE involves a breakpoint, where a further reduction of the residual error does not improve the solution in terms of compatibility with EFIE, which provides a more accurate reference solution. This breakpoint corresponds to the last useful iteration, where the accuracy of CFIE is saturated and a further reduction of the residual error is practically unnecessary. View full abstract»

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  • Overview and Classification of Some Regularization Techniques for the Gauss-Newton Inversion Method Applied to Inverse Scattering Problems

    Publication Year: 2009 , Page(s): 2658 - 2665
    Cited by:  Papers (26)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (304 KB) |  | HTML iconHTML  

    Different regularization techniques used in conjunction with the Gauss-Newton inversion method for electromagnetic inverse scattering problems are studied and classified into two main categories. The first category attempts to regularize the quadratic form of the nonlinear data misfit cost-functional at different iterations of the Gauss-Newton inversion method. This can be accomplished by utilizing penalty methods or projection methods. The second category tries to regularize the nonlinear data misfit cost-functional before applying the Gauss-Newton inversion method. This type of regularization may be applied via additive, multiplicative or additive-multiplicative terms. We show that these two regularization strategies can be viewed from a single consistent framework. View full abstract»

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  • A 3-D Discontinuous Spectral Element Time-Domain Method for Maxwell's Equations

    Publication Year: 2009 , Page(s): 2666 - 2674
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (797 KB) |  | HTML iconHTML  

    A discontinuous spectral element time-domain method is proposed to analyze transient electromagnetic properties of general 3-D structures. This method is advantageous in that its mass matrices are block-diagonal due to the Gauss-Lobatto-Legendre polynomials, and it allows different orders of basis functions for each subdomain. The Riemann solver is employed in the boundary integral terms to communicate fields between adjacent subdomains. Perfectly matched layers are utilized to truncate the computational domain. Galerkin method is used for spatial discretization, and a fourth-order Runge-Kutta scheme is employed for the time integration. The validity of the proposed approach is demonstrated through several numerical examples of initial value problems and scattering problems. View full abstract»

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  • Three New Unconditionally-Stable FDTD Methods With High-Order Accuracy

    Publication Year: 2009 , Page(s): 2675 - 2682
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (412 KB) |  | HTML iconHTML  

    Three novel finite-difference time-domain (FDTD) methods based on the split-step (SS) scheme with high-order accuracy are presented, which are proven to be unconditionally stable. In the first novel method, symmetric operator and uniform splitting are adopted simultaneously to split the matrix derived from the classical Maxwell's equations into six sub-matrices. Accordingly, the time step is divided into six sub-steps. The second and third proposed methods are obtained by adjusting the sequence of the sub-matrices deduced in the first method, so all the novel methods presented in the paper have similar formulations, of which the numerical dispersion errors and the anisotropic errors are lower than the alternating direction implicit finite-difference time-domain (ADI-FDTD) method, the initial SS-FDTD method and the modified SS-FDTD method based on the Strang-splitting scheme. Specifically, for the second method, corresponding to a certain cell per wavelength (CPW), there is a Courant number value making the numerical anisotropic error to be zero, while in the third novel method, corresponding to a certain Courant number value, there exists a CPW making the numerical anisotropic error to be zero. In order to demonstrate the high-order accuracy and efficiency of the proposed methods, numerical results are presented. View full abstract»

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  • Corrected Impulse Invariance Method in Z-Transform Theory for Frequency-Dependent FDTD Methods

    Publication Year: 2009 , Page(s): 2683 - 2690
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (393 KB) |  | HTML iconHTML  

    The classical impulse invariance method in Z-transform theory is found to be incorrect and inaccurate when the impulse response is discontinuous at initial time t = 0 . Such inaccuracy results in higher numerical errors if it is used to develop the update equations for frequency-dependent finite-difference time-domain (FDTD) methods. In this paper, thorough discussions of corrected impulse invariance method in the realm of Z-transform theory for dispersive media are presented. The correction is shown to be necessary for dispersive media which exhibit discontinuity at t = 0 in the time domain susceptibility function. A (corrected) Z-transform table is provided to facilitate the conversion from frequency to Z domain. With the aid of the table, various formulations of frequency-dependent FDTD update equations using both corrected and classical impulse invariance methods are carried out conveniently. Detailed performance measures such as numerical permittivity, leading error term, dispersion relation, normalized phase and attenuation errors as well as memory storage requirements are included along with some extensive numerical comparisons. View full abstract»

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  • A Versatile Split-Field 1-D Propagator for Perfect FDTD Plane Wave Injection

    Publication Year: 2009 , Page(s): 2691 - 2697
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (287 KB) |  | HTML iconHTML  

    A new staggered field design and formulation for the one-dimensional propagator of the total-field/scattered-field source implementation in finite-difference time domain (FDTD) scattering simulations are presented. The new equations are based on split-field Maxwell's equations and the resulting technique extends the functionality of the multipoint auxiliary propagator to sourcing FDTD lattices hosting extended-stencil high-order algorithms. This technique virtually eliminates numerical dispersion, field location and polarization mismatches between propagator and main grid. The resulting machine accuracy-level leakage error from implementing this technique is confirmed for the standard low and high-order FDTD schemes as well as the M24 high-order algorithm. Normalized field leakage for all three algorithm implementations outside the total-field region was measured at below - 295 dB. View full abstract»

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  • Comparison Identities for Wave Propagation in a Time-Varying Plasma Medium

    Publication Year: 2009 , Page(s): 2698 - 2705
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (413 KB) |  | HTML iconHTML  

    An unbounded space-invariant but time-varying medium conserves the wave number k of the wave but alters the frequency of the wave. Thus a switched medium acts like a frequency transformer, the frequencies of the newly created waves (output waves) are easily computed. The amplitudes of the output waves depend on the rise time Tr of the profiles of the parameters of the switched medium. View full abstract»

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  • Recursive Two-Way Parabolic Equation Approach for Modeling Terrain Effects in Tropospheric Propagation

    Publication Year: 2009 , Page(s): 2706 - 2714
    Cited by:  Papers (16)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1535 KB) |  | HTML iconHTML  

    The Fourier split-step method is a one-way marching-type algorithm to efficiently solve the parabolic equation for modeling electromagnetic propagation in troposphere. The main drawback of this method is that it characterizes only forward-propagating waves, and neglects backward-propagating waves, which become important especially in the presence of irregular surfaces. Although ground reflecting boundaries are inherently incorporated into the split-step algorithm, irregular surfaces (such as sharp edges) introduce a formidable challenge. In this paper, a recursive two-way split-step algorithm is presented to model both forward and backward propagation in the presence of multiple knife-edges. The algorithm starts marching in the forward direction until the wave reaches a knife-edge. The wave arriving at the knife-edge is partially-reflected by imposing the boundary conditions at the edge, and is propagated in the backward direction by reversing the paraxial direction in the parabolic equation. In other words, the wave is split into two components, and the components travel in their corresponding directions. The reflected wave is added to the forward-wave in each range step to obtain the total wave. The wave-splitting is performed each time a wave is incident on one of the knife-edges. This procedure is repeated until convergence is achieved inside the entire domain. View full abstract»

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Aims & Scope

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

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Meet Our Editors

Editor-in-Chief                                                 Kwok W. Leung