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Antennas and Propagation, IEEE Transactions on

Issue 5 • Date May 2009

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Displaying Results 1 - 25 of 41
  • Table of contents

    Publication Year: 2009 , Page(s): C1 - 1305
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    Freely Available from IEEE
  • IEEE Transactions on Antennas and Propagation publication information

    Publication Year: 2009 , Page(s): C2
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    Freely Available from IEEE
  • Editorial

    Publication Year: 2009 , Page(s): 1306 - 1308
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    Freely Available from IEEE
  • Low-Profile Equiangular Spiral Antenna Backed by an EBG Reflector

    Publication Year: 2009 , Page(s): 1309 - 1318
    Cited by:  Papers (25)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1998 KB) |  | HTML iconHTML  

    The bi-directional beam from an equiangular spiral antenna (EAS) is changed to a unidirectional beam using an electromagnetic band gap (EBG) reflector. The antenna height, measured from the upper surface of the EBG reflector to the spiral arms, is chosen to be extremely small to realize a low-profile antenna: 0.07 wavelength at the lowest analysis frequency of 3 GHz. The analysis shows that the EAS backed by the EBG reflector does not reproduce the inherent wideband axial ratio characteristic observed when the EAS is isolated in free space. The deterioration in the axial ratio is examined by decomposing the total radiation field into two field components: one component from the equiangular spiral and the other from the EBG reflector. The examination reveals that the amplitudes and phases of these two field components do not satisfy the constructive relationship necessary for circularly polarized radiation. Based on this finding, next, the EBG reflector is modified by gradually removing the patch elements from the center region of the reflector, thereby satisfying the required constructive relationship between the two field components. This equiangular spiral with a modified EBG reflector shows wideband characteristics with respect to the axial ratio, input impedance and gain within the design frequency band (4-9 GHz). Note that, for comparison, the antenna characteristics for an EAS isolated in free space and an EAS backed by a perfect electric conductor are also presented. View full abstract»

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  • Illustrations of New Physical Bounds on Linearly Polarized Antennas

    Publication Year: 2009 , Page(s): 1319 - 1327
    Cited by:  Papers (65)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (982 KB) |  | HTML iconHTML  

    A recent approach to physical bounds on antennas of arbitrary shape is numerically illustrated. In particular, physical bounds for antennas circumscribed by the rectangular parallelepiped, finite cylinders, and planar rectangles are presented. The bounds are verified against numerical results for various small antennas with excellent agreement. View full abstract»

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  • Triple Mode Use of a Single Dielectric Resonator

    Publication Year: 2009 , Page(s): 1328 - 1335
    Cited by:  Papers (14)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1963 KB) |  | HTML iconHTML  

    A single dielectric resonator is used for a triple mode operation in filtering and dual band radiation purposes. A high unloaded quality factor over 2300 at 2.43 GHz is obtained simultaneously with both broadside and omni-directional radiation patterns of 7% and 8% bandwidths around 2.47 and 3.36 GHz, respectively. Series of parametric studies are developed to tune the filter's operating frequency range, to enhance its insertion loss and to obtain a sharp filtering skirt behavior. Finally, measurements of both filter insertion loss and antenna return loss, coupling coefficients and radiation patterns are illustrated for further verification. View full abstract»

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  • Edge Diffraction Suppression in Rectangular Dielectric Resonators for Quality Factor Enhancement Using Artificial Plasma

    Publication Year: 2009 , Page(s): 1336 - 1344
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (863 KB) |  | HTML iconHTML  

    The concept of quality factor enhancement in a two dimensional rectangular dielectric resonator (RDR), based on the phenomenon of edge diffraction suppression by a plasma, is presented. This phenomenon occurs when the plasma exhibits the specific negative permittivity, which makes the RDR separable, i.e., analytically solvable by means of the separation of variables. The Rotman plasma, constituted of metal thin wires is proposed as a practical implementation of this ideal plasma, and the diffraction suppression concept is demonstrated with this plasma by an SIE/MoM approach verified by using a finite element method solver, HFSS. It is shown that a relatively small number of wires (4 times 4) in the plasma is sufficient to mimic a close-to-ideal plasma medium, which suggests a potential for practical applications. This study reveals that the utilization of this plasma allows a strong (high-Q) resonance even for low-permittivity dielectrics otherwise improper to act as resonators. View full abstract»

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  • Performance of a Crossed Exponentially Tapered Slot Antenna for UWB Systems

    Publication Year: 2009 , Page(s): 1345 - 1352
    Cited by:  Papers (20)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1265 KB) |  | HTML iconHTML  

    A compact printed antenna is described that exhibits adequate transient performance for ultrawideband (UWB) applications and it is further adequate for polarization diversity schemes. The antenna is based on an original combination of two crossed exponentially tapered slots plus a star-shaped slot to produce a stable radiation pattern with very stable polarization over the 3.1-10.6 GHz FCC assigned band. Results are confirmed with measurements. Figures of merit like output pulse fidelity and time window containing 90% of the transmitted energy are analyzed over the entire solid angle and showed to remain quite stable, in line with envisaged UWB system requirements. Compact dual-antenna arrangements are also analyzed in view of potential use for UWB multiple-input-multiple-output implementations. View full abstract»

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  • Investigations on Ultrawideband Pentagon Shape Microstrip Slot Antenna for Wireless Communications

    Publication Year: 2009 , Page(s): 1353 - 1359
    Cited by:  Papers (12)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1288 KB) |  | HTML iconHTML  

    An ultrawideband (UWB) pentagon shape planar microstrip slot antenna is presented that can find applications in wireless communications. Combination of the pentagon shape slot, feed line and pentagon stub are used to obtain 124% (2.65-11.30 GHz) impedance bandwidth which exceeds the UWB requirement of 110% (3.10-10.60 GHz). A ground plane of 50 mm × 80 mm size is used which is similar to wireless cards for several portable wireless communication devices. The proposed antenna covers only the top 20 mm or 25% of the ground plane length, which leaves enough space for the RF circuitry. Three variations of the antenna design using the straight and rotated feed lines on two different substrates are considered. Effect of the conducting reflecting sheet on back of the antenna is investigated, which can provide directional radiation patterns but with reduced matching criteria. Finally, experimental verification of the fabricated antenna for its impedance bandwidth is carried out, which shows agreement with the simulated data. View full abstract»

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  • A Miniaturized Ground Edge Current Choke—Design, Measurement, and Applications

    Publication Year: 2009 , Page(s): 1360 - 1366
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (811 KB) |  | HTML iconHTML  

    We propose a miniaturized microwave current choke for blocking the current flowing along the edge of a substrate's ground plane. The proposed current choke is composed of a printed inductor and a printed capacitor, which possesses a size much smaller than a conventional quarter-wavelength current choke. By introducing the choke at one side of the ground plane, an effective electrical open circuit is performed for reflecting the ground edge current. The size of the proposed ground edge current choke (GECC) is as small as around 0.06 wavelength in free space. Two applications of the GECC are presented in this paper. The first is the radiation pattern regulation of a printed monopole antenna with long ground plane. The GECC in this application reflects the induced traveling-wave current along the ground plane edge and changes it to a standing-wave one, thus regulating the tilted radiation pattern due to the traveling-wave current to a broadside pattern. The other application is the decoupling of two nearby monopole antennas. By placing the proposed compact GECC in between the antennas, it is found that the isolation between the antenna ports can be enhanced from 8 dB to 32 dB. The experimental results agree well with the simulation, which demonstrate the feasibility of the proposed GECC. View full abstract»

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  • Cassegrain Antenna With Hybrid Beam Steering Scheme for Mobile Satellite Communications

    Publication Year: 2009 , Page(s): 1367 - 1372
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (919 KB) |  | HTML iconHTML  

    A hybrid antenna (HA) with a modified beam steering method is proposed. This antenna has a Cassegrain structure composed of two reflectors and a feeder. The parabolic-shaped main reflector is designed for high gain, while the subreflector is rotational and flat. The feeder is a phased array with arbitrary shaped aperture and 20 element antennas. The HA is capable of two-dimensional beam steering by means of two operations: rotation of the subreflector and phase control of the feed array. The subreflector is small in size and weight, so it can provide rapid beam scanning. Designed to be loaded in vehicles, the HA and can communicate with satellites on the move by tracking the beam control of the feed array. A prototype of the HA is fabricated with aluminum using a machining center operated by computerized numerical control. The prototype is operated at Ka-band for TX and K-band for RX with gains of 47 dBi and 44.4 dBi, respectively, at a steering angle of 0 deg. The two-dimensional beam steering within plusmn2deg with respect to 45deg elevation is realized by the subreflector and feed array. All radiation patterns in the beam steering zone meet ITU-R s.465-5 regulations. View full abstract»

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  • Printed \lambda /8 -PIFA for Penta-Band WWAN Operation in the Mobile Phone

    Publication Year: 2009 , Page(s): 1373 - 1381
    Cited by:  Papers (76)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1713 KB) |  | HTML iconHTML  

    A small-size printed planar inverted-F antenna (PIFA) operated at its one-eighth wavelength (lambda/8) mode as the fundamental resonant mode for achieving WWAN (wireless wide area network) operation in the mobile phone is presented. The proposed PIFA has a simple structure of comprising two radiating strips of length about lambda/8 at 900 MHz and is fed using a coupling feed. Compared to the traditional PIFA using a direct feed, the coupling feed greatly decreases the very large input impedance seen at the lambda/8 mode for the traditional PIFA and results in successful excitation of the lambda/8 mode for the proposed PIFA. Two lambda/8 modes are generated by the two radiating strips and occur at close frequencies at about 900 MHz to form a wide lower band to cover GSM850/900 operation. The two radiating strips also generate two higher-order modes or lambda/4 modes at about 1900 MHz to form a wide upper band for GSM1800/1900/UMTS operation. Penta-band WWAN operation is hence achieved, yet the proposed PIFA only occupies a small printed area of 15times31 mm2 or 465 mm2 on the system circuit board of the mobile phone, which is about the smallest for the internal uniplanar printed antenna capable of penta-band operation that have been reported. Details of the proposed PIFA are presented. The specific absorption rate (SAR) and hearing aid compatibility (HAC) results for the proposed PIFA are also analyzed. View full abstract»

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  • Multilevel Plane Wave Based Near-Field Far-Field Transformation for Electrically Large Antennas in Free-Space or Above Material Halfspace

    Publication Year: 2009 , Page(s): 1382 - 1390
    Cited by:  Papers (17)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (931 KB) |  | HTML iconHTML  

    A recently presented fully probe-corrected near-field far-field transformation employing plane wave expansion and diagonal translation operators enables near-field far-field transformation for arbitrary measurement contours and arbitrary antennas. A multilevel extension, inspired by the multilevel fast multipole method, is presented that is suitable for the efficient transformation of electrically large antennas with a size of tens or even hundreds of wavelengths. The measurement points are grouped in a multilevel fashion and translations are carried out to the box centers on the highest level only. The plane waves are processed through the different levels to the measurement points using a disaggregation and anterpolation procedure resulting in a reduced overall complexity. In the second part of this paper, the influence of perfectly conducting ground planes and dielectric halfspaces, as an approximation for ground effects in a real measurement setup, is investigated. As such ground reflected waves are assumed, which propagate from the investigated antenna to the field probe and add to the direct wave contributions. The far-field conditions required for these assumptions are achieved by a source box grouping scheme. By this extension ground effects are directly considered within the near-field far-field transformation. Transformation results using simulated and measured near-field data are shown. View full abstract»

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  • Effect of Coupling Phase on Mutual Injection Locking Range in Coupled Oscillator Arrays

    Publication Year: 2009 , Page(s): 1391 - 1398
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (746 KB) |  | HTML iconHTML  

    The performance of a coupled oscillator array depends critically on the coupling network. Determination of the optimal coupling phase depends on the oscillator equivalent circuit and the location of mutual coupling between the oscillators. In this paper, the authors examine the effects of coupling phase on the mutual injection locking range. Three element coupled oscillator arrays (COAs) were mutually coupled at two different locations, with each coupling location presenting a different resonance to the coupling network, and the optimal coupling phase required to generate a linear phase shift in the range of -90deg to 90deg was determined. For each coupling location, when the coupling phase was off by 180deg , the arrays were shown to lock with a limited range and operate in a mode other than the in-phase mode. View full abstract»

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  • On the Direction of Arrival (DoA) Estimation for a Switched-Beam Antenna System Using Neural Networks

    Publication Year: 2009 , Page(s): 1399 - 1411
    Cited by:  Papers (11)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1690 KB) |  | HTML iconHTML  

    A generic direction of arrival (DoA) estimation methodology is presented that is based on neural networks (NNs) and designed for a switched-beam system (SBS). The method incorporates the benefits of NNs and SBSs to achieve DoA estimation in a less complex and expensive way compared to the corresponding widely known super resolution algorithms. The proposed technique is step-by-step developed and thoroughly studied and explained, especially in terms of the beam pattern structure and the neuro-computational procedures. Emphasis is given on the direct sequence code division multiple access (DS-CDMA) applications, and particularly the Universal Mobile Telecommunication System (UMTS). Extensive simulations are realized for each step of the method, demonstrating its performance. It is shown that a properly trained NN can accurately find the signal of interest (SoI) angle of arrival at the presence of a varying number of mobile users and a varying SoI to interference ratio. The proposed NN-SBS DoA estimation method can be applied to current cellular communications base stations, promoting the wider use of smart antenna beamforming. View full abstract»

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  • Mean-Field Electrodynamic Theory of Aligned Carbon Nanotube Composites

    Publication Year: 2009 , Page(s): 1412 - 1419
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (683 KB) |  | HTML iconHTML  

    We propose an improved effective-medium theory to study the interaction of the electromagnetic field with carbon nanotubes composites. The axial response of the tube is obtained by an approximate solution of the parallel polarization scattering by spheroidal-shape inclusions, which takes into account the first-order geometric resonances and intra/inter-band transitions. The proposed theory is in conformity with experimental results published elsewhere. Mathematical derivations are provided to demonstrate that aligned carbon nanotube composites can support negative-refraction wave propagation under certain conditions. The theory is employed to perform a statistical analysis of carbon nanotube composites using practical probability distributions. View full abstract»

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  • Efficient Analysis of Aperture Antennas on Generally Shaped Convex Multilayered Surfaces Using a Hybrid SD-UTD Method

    Publication Year: 2009 , Page(s): 1420 - 1431
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1250 KB) |  | HTML iconHTML  

    A novel hybrid method is described for analyzing convex multilayered conformal array antennas. The hybrid method is based on the spectral domain approach in combination with the ray-based uniform theory of diffraction (UTD) method. The analysis is divided in two parts. First, the spectral domain approach is accelerated by using an asymptotic extraction technique where the extracted term of the Green's function is calculated using UTD. It is shown that this new approach results in significant acceleration of the existing spectral domain algorithm without losing accuracy. The modified spectral domain method is then used in the second part where generally shaped convex multilayered surfaces are analyzed by using sets of canonically shaped surfaces (spheres and/or circular cylinders). Their radii are obtained using the UTD formulation, which contains important information such as distance and curvature of the generally shaped surface along each geodesic. The results obtained using the new algorithm are compared to the available results (calculated and measured) for different conformal antennas, showing very good agreement. View full abstract»

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  • A Radially-Dependent Dispersive Finite-Difference Time-Domain Method for the Evaluation of Electromagnetic Cloaks

    Publication Year: 2009 , Page(s): 1432 - 1441
    Cited by:  Papers (25)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1011 KB) |  | HTML iconHTML  

    A radially-dependent dispersive finite-difference time-domain (FDTD) method is proposed to simulate electromagnetic cloaking devices. The Drude dispersion model is applied to model the electromagnetic characteristics of the cloaking medium. Both lossless and lossy cloaking materials are examined and their operating bandwidth investigated. It is demonstrated that the perfect ldquoinvisibilityrdquo of electromagnetic cloaks is only available for lossless metamaterials and within an extremely narrow frequency band. View full abstract»

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  • FDTD-PWS Scheme and Its Application to Analysis of Focusing Properties of Dielectric Lens

    Publication Year: 2009 , Page(s): 1442 - 1451
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1049 KB) |  | HTML iconHTML  

    The focusing properties of lens are studied by a hybrid scheme that involves the finite-difference time-domain (FDTD) method for the aperture-plane field computation and the plane wave spectrum (PWS) method for the transformation from the aperture-plane field to the focal-plane field. To demonstrate the accuracy and efficiency of this new scheme, a Ka-band lens antenna is simulated and fabricated as an example. Subsequently, the near-field-region and the Fresnel-region fields of this lens antenna are measured by the planar-near-field (PNF) method. It is found that the results obtained by the FDTD-PWS scheme are in good agreement with the measured data. Furthermore, the numerical results and the computational requirements of this new scheme are compared with those of the near-field to near-field (NF-NF) transformation, the aperture integration (AI) method, the geometrical optics (GO)-physical optics (PO) method, and the full FDTD simulation. Both the central processing unit (CPU) time and memory requirement can be reduced efficiently. Finally, the effects of several fundamental issues, including spatial sample parameters, lens material, operating frequency, and designed focal length, on the accuracy of the proposed scheme and on the focusing properties of the lens are investigated. View full abstract»

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  • Higher Order Hybrid FEM-MoM Technique for Analysis of Antennas and Scatterers

    Publication Year: 2009 , Page(s): 1452 - 1460
    Cited by:  Papers (19)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1468 KB) |  | HTML iconHTML  

    A novel higher order large-domain hybrid computational electromagnetic technique based on the finite element method (FEM) and method of moments (MoM) is proposed for three-dimensional analysis of antennas and scatterers in the frequency domain. The geometry of the structure is modeled using generalized curved parametric hexahedral and quadrilateral elements of arbitrary geometrical orders. The fields and currents on elements are modeled using curl- and divergence-conforming hierarchical polynomial vector basis functions of arbitrary approximation orders, and the Galerkin method is used for testing. The elements can be as large as about two wavelengths in each dimension. As multiple MoM objects are possible in a global exterior region, the MoM part provides much greater modeling versatility and potential for applications, especially in antenna problems, than just as a boundary-integral closure to the FEM part. The examples demonstrate excellent accuracy, convergence, efficiency, and versatility of the new FEM-MoM technique, and very effective large-domain meshes that consist of a very small number of large flat and curved FEM and MoM elements, with p-refined field and current distributions of high approximation orders. The reduction in the number of unknowns is by two orders of magnitude when compared to available data for low-order FEM-MoM modeling. View full abstract»

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  • Empirical Near Ground Path Loss Modeling in a Forest at VHF and UHF Bands

    Publication Year: 2009 , Page(s): 1461 - 1468
    Cited by:  Papers (16)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (934 KB) |  | HTML iconHTML  

    Near ground radio wave propagation is examined in a tropical plantation experimentally at VHF and UHF bands. The propagation loss with forest depth is empirically analyzed using an integrated model combining both the foliage induced effect and the ground effect. Several well-known empirical foliage models are compared and analyzed. It is observed that the fitted ITU-R model taking into account the ground reflection, can provide a close approximation to the path loss in a tropical palm plantation. However, the accuracy of this model becomes poor when lateral wave dominates in the VHF band. A modification to the ITU-R model is then proposed taking into consideration the lateral wave effect. The modified model is verified using measured and published data, and found to have higher accuracy for large foliage depth in the VHF band as compared to the existing empirical foliage models. View full abstract»

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  • Speed-Up Techniques for Ray Tracing Field Prediction Models

    Publication Year: 2009 , Page(s): 1469 - 1480
    Cited by:  Papers (14)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3056 KB) |  | HTML iconHTML  

    Despite their good performance, the widespread diffusion of ray tracing field-prediction models is still limited due to their high complexity and high computation time. In this paper, two different classes of methods for speeding up ray tracing urban field prediction are proposed, aimed at reducing the size of the input database and the number of rays to be handled by the algorithm. With the proposed techniques, a great computation time reduction can be achieved without sensibly affecting the accuracy of the prediction. View full abstract»

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  • Transmission Through Layered Media With Rough Boundaries: First-Order Perturbative Solution

    Publication Year: 2009 , Page(s): 1481 - 1494
    Cited by:  Papers (13)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (697 KB) |  | HTML iconHTML  

    We investigate analytically the fully polarimetric electromagnetic wave propagation through a 3-D layered structure. In the framework of the first-order limit of the perturbation theory, a transmission model for a layered structure with an arbitrary number of rough interfaces is developed and an elegant closed-form solution is obtained. The final expressions, in terms of generalized reflection/transmission coefficients, provide parametrically a direct characterization of the scattering properties of the layered structure in terms of the structure's (geometric and electromagnetic) parameters. In addition, we point out the complementary character of the obtained scattering solution with respect to the existing one. Finally, we demonstrate that our solution satisfies the reciprocity principle. View full abstract»

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  • Bidirectional Analytic Ray Tracing for Fast Computation of Composite Scattering From Electric-Large Target Over a Randomly Rough Surface

    Publication Year: 2009 , Page(s): 1495 - 1505
    Cited by:  Papers (21)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2219 KB) |  | HTML iconHTML  

    The bidirectional analytic ray tracing (BART) method is developed to rapidly calculate composite scattering from three-dimensional (3D) electrically large complex targets above a randomly rough surface. Ray tracing is carried out both along the incident (forward) direction and converse direction of scattering (backward) recording different orders of ray illumination on each facet or edge of the target and surface. Once a pair of forward and backward rays meet on a facet/edge, a scattering term is constructed using the diffused scattering/diffraction of this facet/edge and all reflections occurred on the tracing paths. The rough surface is modeled with ldquorough facetsrdquo including coherent scattering and diffused incoherent scattering, which can be directly calculated according to the IEM (integral equation method) of a randomly rough surface. Analytic tracing of polygon ray tubes is developed to precisely calculate the illumination and shadowing of facets, which exempt large patches of the target from any finer meshing. It significantly reduces the complexity relevant to the target electric-size. Higher orders of scattering and, in particular, interactions between the target and rough surface are then taken into account. The accuracy and performance of BART is validated and evaluated by comparing with exact computational electromagnetic methods for electrically small targets. Numerical examples of angularly composite scattering from a three-dimensional electrically large, e.g., a ship-like target over a randomly rough surface are presented and discussed. View full abstract»

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  • Time Domain Integral Equation Analysis of Scattering From Composite Bodies via Exact Evaluation of Radiation Fields

    Publication Year: 2009 , Page(s): 1506 - 1520
    Cited by:  Papers (27)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1362 KB) |  | HTML iconHTML  

    A novel marching on in time and Poggio-Miller-Chang-Harrington-Wu-Tsai (PMCHWT)-based time domain integral equation solver for analyzing transient scattering from composite multiregion structures comprising homogeneous penetrable volumes and perfectly conducting surfaces is presented. To render the marching on in time procedure stable, observer and source integrals are approximated via multipoint collocation and evaluated in closed form. The proposed scheme avoids the costly evaluation of five dimensional integrals required in full space-time Galerkin schemes, and proves to be stable for all targets investigated, including coated perfect electrically conducting surfaces and multiregion penetrable volumes. View full abstract»

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Aims & Scope

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

Full Aims & Scope

Meet Our Editors

Editor-in-Chief                                                 Kwok W. Leung