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Antennas and Propagation, IEEE Transactions on

Issue 6  Part 2 • Date June 2007

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Displaying Results 1 - 25 of 35
  • Table of contents

    Publication Year: 2007 , Page(s): C1 - 1681
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  • IEEE Transactions on Antennas and Propagation publication information

    Publication Year: 2007 , Page(s): C2
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  • Design of Compact Dual Band High Directive Electromagnetic Bandgap (EBG) Resonator Antenna Using Artificial Magnetic Conductor

    Publication Year: 2007 , Page(s): 1682 - 1690
    Cited by:  Papers (17)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1459 KB) |  | HTML iconHTML  

    A compact high directive EBG resonator antenna operating in two frequency bands is described. Two major contributions to this compact design are using single layer superstrate and using artificial surface as ground plane. To obtain only the lower operating frequency band using superstrate layer is enough, but to extract the upper operating frequency band both superstrate layer and artificial surface as ground plane are necessary. Therefore, design of a superstrate to work in two frequency bands is very important. Initially, using appropriate frequency selective surface (FSS) structure with square loop elements, we design an optimum superstrate layer for each frequency band separately to achieve maximum directivity. Also, to design an artificial surface to work in the upper frequency band we use a suitable FSS structure over dielectric layer backed by PEC. Next, by using the idea of FSS structure with double square loop elements we propose FSS structure with modified double square loop elements, so that it operates in both of the desired operating frequency bands simultaneously. Finally, the simulation results for two operating frequency bands are shown to have good agreement with measurements. View full abstract»

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  • Radiation Characteristics of a Microstrip Patch Over an Electromagnetic Bandgap Surface

    Publication Year: 2007 , Page(s): 1691 - 1697
    Cited by:  Papers (27)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (805 KB) |  | HTML iconHTML  

    Radiation characteristics of a microstrip patch over an electromagnetic bandgap (EBG) substrate are investigated in this paper. This paper focuses on a mushroom-type EBG structure, although the design is applicable to various EBG profiles. The patch antenna is modeled as a half-wavelength resonator of an EBG-loaded microstrip transmission line. Through a full-wave eigenmode analysis of a microstrip line on an EBG structure, it is found that the resonant patch will not see a high-impedance surface (HIS), but rather it is coupled to the EBG structure as an open cavity resonator. Due to strong near-field coupling, the propagation characteristics including the bandgap zones are very different with or without the patch cover. The use of an EBG structure as a bulk material for antennas is seen inappropriate. The EBG surface is found to have the effect of reducing the patch resonant length and bandwidth. A prototype of a microstrip line proximity fed to a patch antenna is fabricated and tested to verify the analysis. View full abstract»

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  • Theory and Simulations of a Conformal Omni- Directional Subwavelength Metamaterial Leaky-Wave Antenna

    Publication Year: 2007 , Page(s): 1698 - 1708
    Cited by:  Papers (11)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1586 KB) |  | HTML iconHTML  

    The detailed theory of a single subwavelength conformal radiator that exploits the resonant properties of thin cylindrical metamaterial shells supporting leaky waves is presented. It is shown and reviewed analytically and numerically how a circularly symmetric resonant leaky mode may be supported by a properly designed subwavelength homogenous cylindrical shell of low negative permittivity. Some physical insights are provided and numerical simulations with a feed point, considering also the finite-ness of the antenna in the longitudinal direction, are presented and discussed. Moreover, possibilities and limitations of a practical realization of this setup are mentioned, considering in details the possible anisotropies in the metamaterials. View full abstract»

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  • Equivalent Relations Between Interchannel Coupling and Antenna Polarization Coupling in Polarization Diversity Systems

    Publication Year: 2007 , Page(s): 1709 - 1715
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (598 KB) |  | HTML iconHTML  

    Both the interchannel coupling (CC) among multiple compact circuitry channels and the antenna polarization coupling (APC) due to angular deviation of antennas (ADA) in diversity systems cannot be neglected in practice. The effects of these two problems are considered in this paper. The investigation of the CC in a two-branch orthogonal polarization antenna diversity system is extended to the case of a general multibranch polarization antenna diversity system, and the CC is investigated together with APC by applying a network theory framework. Their effects on both the correlation and the mean power ratio among received signals are obtained. It is found that the effects of both kinds of couplings as well as that of the combining signal processing on the received signals can be considered as a series of weightings. Two equivalent relations among APC, CC, and ADA are developed. Such equivalences reveal insights into CC from the point of view of antennas and provide additional degree-of-freedom for system optimization to improve the diversity performance. Furthermore, two kinds of compensation techniques are also developed to mitigate the APC and CC, as well as to enhance the diversity performance. Finally, some numerical results are presented to validate the analyses. View full abstract»

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  • Low-Dimensional SDP Formulation for Large Antenna Array Synthesis

    Publication Year: 2007 , Page(s): 1716 - 1725
    Cited by:  Papers (9)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (473 KB) |  | HTML iconHTML  

    Bounding the sidelobe and mainlobe levels of an array with complex weights is attractive in that it allows direct control of the radiation pattern. In this paper we propose an efficient beamforming technique for synthesizing the patterns of large arrays with bound constraints on the sidelobe and mainlobe levels. It is shown that the pattern synthesis problem can be posed as a convex semi-infinite program (SIP) which is then turned into a semi-definite program (SDP) via a novel linear matrix inequality (LMI) characterization of semi-infinite trigonometric polynomial constraints. In contrast to existing SDP formulations which require a large number of additional variables, our SDP representation only uses a minimal number of additional variables. This subsequently enables the design of patterns for arrays with several hundred elements to be efficiently achieved on a standard personal computer using existing SDP solvers. View full abstract»

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  • Optimal Noise Matching for Mutually Coupled Arrays

    Publication Year: 2007 , Page(s): 1726 - 1731
    Cited by:  Papers (27)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (345 KB) |  | HTML iconHTML  

    From classical two-port noise theory, the noise figure of an amplifier is minimized when a source is matched to a particular optimal reflection coefficient at the amplifier input. In this paper, we show that this result extends in a natural way to the multiport case, with a coupled N-port source network such as an array antenna connected by a multiport matching network to the inputs of N low-noise amplifiers. For optimal noise performance, the matching network must decouple the array and present isolated, individually noise-matched ports to the amplifier inputs. View full abstract»

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  • Reduction of Mutual Coupling Between Closely-Packed Antenna Elements

    Publication Year: 2007 , Page(s): 1732 - 1738
    Cited by:  Papers (102)  |  Patents (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (927 KB) |  | HTML iconHTML  

    A simple ground plane structure that can reduce mutual coupling between closely-packed antenna elements is proposed and studied. The structure consists of a slitted pattern, without via's, etched onto a single ground plane and it is therefore low cost and straightforward to fabricate. It is found that isolations of more than -20 dB can be achieved between two parallel individual planar inverted-F antennas (PIFAs) sharing a common ground plane, with inter-antenna spacing (center to center) of 0.116 lambdao and ground plane size 0.331lambdao 2. At 2.31 GHz it is demonstrated that this translates into an edge to edge separation between antennas of just 10 mm. Similarly the structure can be applied to reduce mutual coupling between three or four radiating elements. In addition the mutual coupling between half wavelength patches and monopoles can also be reduced with the aid of the proposed ground plane structure. Results of parametric studies are also given in this paper. Both simulation and measurement results are used to confirm the suppression of mutual coupling between closely-packed antenna elements with our slitted ground plane. View full abstract»

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  • In-Line Series-Feed Collinear Slot Array Fed by a Coplanar Waveguide

    Publication Year: 2007 , Page(s): 1739 - 1744
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (556 KB) |  | HTML iconHTML  

    The in-line series-feed collinear slot array antenna fed by a coplanar waveguide is investigated thoroughly. Radiating elements are placed end-to-end along the shunt slotline pair transverse to the feedline. This simple linear array structure increases the antenna gain and shapes the H-plane pattern. The shunt slot- line pair can be terminated by either short or open circuit. The short ends, the slotline circular open stubs, and the directly-truncated open ends are used as terminations. Design guidelines for the three cases are given separately. A reflector-backed arrangement, with which the proposed antennas would be able to radiate unidirectional patterns, is also discussed. Experimental results, which agree well with the simulated ones, verify the performances of the proposed antennas. View full abstract»

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  • Parallel Genetic-Algorithm Optimization of Shaped Beam Coverage Areas Using Planar 2-D Phased Arrays

    Publication Year: 2007 , Page(s): 1745 - 1753
    Cited by:  Papers (23)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1392 KB) |  | HTML iconHTML  

    A parallel genetic algorithm (GA) optimization tool has been developed for the synthesis of arbitrarily shaped beam coverage using planar 2D phased-array antennas. Typically, the synthesis of a contoured beam footprint using a planar 2D array is difficult because of the inherently large number of degrees of freedom involved (in general, the amplitude and phase of each element must be determined). We make use of a parallel GA tool in this study to compensate for this aspect of the design problem. The algorithm essentially compares a desired pattern envelope with that of trial arrays, and quantifies the effectiveness or desirability of each test case via a fitness function. The GA uses this information to rank and select subsequent arrays over a given number of generations via the conventional stochastic operators, i.e., selection, crossover, and mutation. Each fitness evaluation of a trial pattern is done on a node of the aerospace fellowship cluster supercomputer, which increases the speed of the algorithm linearly with the number of nodes. Because of the continuous nature of the parameters for this optimization problem, a real parameter encoding scheme is employed for the GA chromosome in order to avoid the quantization errors associated with a binary representation. A benchmark 10 times 10 (100) element array is employed, and various results of optimized coverage patterns are shown herein to illustrate the effectiveness and validity of the technique. View full abstract»

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  • Use of the Coupling Between Elements of the Vertical Antenna Array of LCRs to Gain Radiation Efficiency for UWB Pulses

    Publication Year: 2007 , Page(s): 1754 - 1759
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (932 KB) |  | HTML iconHTML  

    The inductance of large current radiators (LCRs) can be reduced by stacking several of them as a vertical array. The reduced inductance permits a shorter rise time for the driving current. Both theory and experimental data show that the radiated field strengths are increased considerably for a fixed, small driving voltage. View full abstract»

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  • Wideband Reconfigurable Rolled Planar Monopole Antenna

    Publication Year: 2007 , Page(s): 1760 - 1767
    Cited by:  Papers (11)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1417 KB) |  | HTML iconHTML  

    A novel technique to reconfigure the frequency range of a planar monopole antenna is presented. By adjusting the degree of spiral tightness, a shift of the well-matched operating frequency range is achieved. The proposed antenna is capable of covering the frequencies in the range from 2.9 to 15 GHz, depending on the degree of spiral tightness. The antenna yields a high-efficiency across the full operating bandwidth. Radiation patterns show good omni-directional features in all primary cuts and remain relatively stable with the change of antenna configuration, so that it is a remarkable candidate for indoor or mobile applications where a large frequency range and omnidirectional radiation are required. View full abstract»

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  • Dielectric-Covered Dual-Slot Antenna for Dualband Applications

    Publication Year: 2007 , Page(s): 1768 - 1773
    Cited by:  Papers (13)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (448 KB) |  | HTML iconHTML  

    A dualband antenna that consists of two radiating slots is investigated in this paper. The slots are cut onto an L-probe-fed hollow rectangular conducting cavity, which is covered by a protective dielectric layer. The two slots give two resonant modes that lead to a dualband operation. It is very favorable that the frequencies of the two resonant modes can be adjusted independently, which greatly facilitates the dual- band design. To demonstrate the idea, a dualband antenna for 2.4/5.2-GHz IEEE802.11a/b WLAN applications is designed. The return loss, radiation pattern, gain, and radiation efficiency of the antenna are studied. Reasonable agreement between simulation and experiment is obtained. View full abstract»

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  • Analysis and Application of an On-Package Planar Inverted-F Antenna

    Publication Year: 2007 , Page(s): 1774 - 1780
    Cited by:  Papers (7)  |  Patents (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1173 KB) |  | HTML iconHTML  

    An on-package planar inverted-F antenna (PIFA) is described. The on-package PIFA consists of a single folded metal plate and has several advantages, including small size, light weight, low cost, and ease of fabrication. The antenna radiation pattern is omnidirectional in the H-plane. The coupling effect between the on-package PIFA and the radio-frequency (RF) components in the shielding package was studied. The antenna performance rarely changes and the isolation between the antenna and the RF components can be maximized when the locations of the components are appropriately arranged in the package. Finally, a wireless local-area network (WLAN) front-end module (FEM) including the switch, low-pass filter (LPF), bandpass filter (BPF), and power amplifier (PA), is embedded into the shielding package of the antenna. The error vector magnitude (EVM) of the resultant antenna integrated FEM, together with a WLAN card containing the baseband/medium-access control (MAC) circuitry, is tested. Good performance is obtained, showing the usability of the proposed antenna configuration. View full abstract»

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  • The Measured Electric Field Spatial Distribution Within A Metamaterial Subwavelength Cavity Resonator

    Publication Year: 2007 , Page(s): 1781 - 1788
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (983 KB) |  | HTML iconHTML  

    Through experimental investigation, a thin subwavelength cavity resonator was physically realized using a bilayer structure composed of air and a negative permeability metamaterial structure one unit cell in thickness. We designed and built the metamaterial slab with periodic metallic ring structures and measured the spatial electric field magnitude in a cavity formed from this slab and a region of air, showing that a subwavelength cavity can be realized. The measured electric field magnitude distribution in the cavity matched very well with effective medium theory, showing that even a slab one unit cell in thickness may be effectively equivalent to a thin homogeneous medium as far as the construction of a sub-wavelength cavity is concerned, provided that the unit cell size is significantly smaller than the free space wavelength. View full abstract»

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  • Frequency and Polarization Transformer: Transverse Modes: I Zero Rise Time

    Publication Year: 2007 , Page(s): 1789 - 1796
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (963 KB) |  | HTML iconHTML  

    A frequency transformer that converts a linearly polarized standing wave into frequency-shifted extraordinary (X) standing waves is considered. The transformer is a one-dimensional cavity in which a magnetoplasma, that supports "transverse modes," is created. Theoretical derivation for the case of sudden and uniform creation of the magnetoplasma is given. It is shown that the switching would result in transformation of the original source wave into three new waves, each having unique frequency, amplitude, and phase. One of these modes is a DC component of zero frequency called the wiggler mode having a wiggler electric as well as a wiggler magnetic component. The wiggler electric field is the unique aspect of the switching problem studied in this paper. A few illustrative results are presented as graphs and tables to illustrate the effects of source and system parameters. They include a case of conversion from linear to circular polarization. View full abstract»

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  • Uniform Asymptotic Expansion of the Associated Legendre Function to Leading Term for Complex Degree and Integral Order

    Publication Year: 2007 , Page(s): 1797 - 1803
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (681 KB) |  | HTML iconHTML  

    The associated Legendre function arises naturally in the study of spherical waves. Since in practical applications it is most often symbolically represented by Pn m(xi) for m les n and Pn m(xi) equiv 0 for m > n where m is the integer order and n is the integer degree, this form will be employed to develop the uniform asymptotic expansion. The considerable extent to which this function appears in literature substantiates its importance in engineering and science, and particularly to spherical harmonics. In his book, "Partial Differential Equations in Physics" Sommerfeld covers a variety of subjects including spherical harmonics, and gives a detailed account of obtaining an expansion of the associated Legendre function, Pn m(cos(thetas)), by the method of steepest descents over the interval 0 les thetas les pi. The results he obtains are quite accurate for n Gt m except as thetas approaches the critical points, thetas rarr 0 or thetas rarr pi. Beginning with the same integral representation of the associated Legendre function with integer order and degree that Sommerfeld employed, a uniform asymptotic expansion is found that is applicable to the neighborhoods of thetas = 0 and thetas = pi and that becomes increasingly more accurate as n increases beyond m. Furthermore, the accuracy of the resulting uniform asymptotic expansion remains for real degree and complex degree as well. The results are plotted in order to assess the accuracy and the domain of validity of the uniform asymptotic expansion. The results of the uniform asymptotic expansion are also compared to the available approximation of the associated Legendre function given in terms of Bessel functions for small values of thetas. View full abstract»

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  • A W-Band Polarization Converter and Isolator

    Publication Year: 2007 , Page(s): 1804 - 1809
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (580 KB) |  | HTML iconHTML  

    A 95-GHz printed low-loss linear-to-circular polarizer is designed as a component of an active direct-detection millimeter-wave imaging system. The periodic printed grid structure presents different reactances to the TE and TM polarizations, resulting in equal amplitude and phase quadrature upon transmission through four parallel grids. The polarizer is measured in both a Gaussian beam system and a plane wave system, and demonstrates an axial ratio of 0.23 dB, polarization isolation of 38 dB, and transmission loss of 0.3 dB for normal incidence. The quarter-wave plate is characterized up to plusmn35deg off the optical axis, and exhibits an axial ratio better than 1 dB up to plusmn17deg off the optical axis. View full abstract»

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  • Massively Parallel Fast Multipole Method Solutions of Large Electromagnetic Scattering Problems

    Publication Year: 2007 , Page(s): 1810 - 1816
    Cited by:  Papers (20)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1317 KB) |  | HTML iconHTML  

    We describe a massively parallel version of the single-level fast multipole method (FMM) that employs the fast Fourier transform (FFT) for the translation stage. The proposed FMM-FFT method alleviates the communication bottleneck and has a lower complexity, O(N4/3 log2/3 N), as compared to the conventional single level FMM which scales as O(N3/2), where N is the number of unknowns. Through numerical examples we demonstrate that the proposed parallel fast multipole method yields a faster solution time than its multilevel counterpart for very large problems in a distributed memory parallel setting. View full abstract»

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  • Scattering from 3-D Inhomogeneous Chiral Bodies of Arbitrary Shape by the Method of Moments

    Publication Year: 2007 , Page(s): 1817 - 1825
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (661 KB) |  | HTML iconHTML  

    A method of moments (MoM) solution is presented for the problem of electromagnetic scattering by a three-dimensional (3D) inhomogeneous chiral scatterer illuminated by an arbitrary incident field. The volume equivalence principle was used to obtain coupled integral equations for equivalent volume currents. These integral equations were then solved numerically using MoM. The volume of the scatterer was modeled by tetrahedral cells, and face-based expansion functions were used to approximate the equivalent currents. Computed results are in very good agreement with exact data or other published data. View full abstract»

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  • Ultrawideband Optimized Profile Monopole Antenna by Means of Simulated Annealing Algorithm and the Finite Element Method

    Publication Year: 2007 , Page(s): 1826 - 1832
    Cited by:  Papers (14)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1534 KB) |  | HTML iconHTML  

    Monopole antennas with an optimized profile are described. They are designed by means of a global optimization using the simulated annealing algorithm and the Finite Element Method. Two designs are presented. The first optimized profile monopole is designed to obtain the lowest return losses over the extremely high bandwidth that lies between 4 GHz and 20 GHz. Better than 17 dB return losses are obtained in all the bandwidth. This initial result is the basis for a more detailed work. The second antenna is designed to optimize return losses in the 2 to 11 GHz band. This frequency band has been chosen to cover the definition of ultrawideband (UWB). Return losses of less than 24 dB have been achieved in the whole band in the simulation step using an infinite ground plane. A prototype has been built, measured and resimulated. Return losses of less than 20 dB have been measured in the whole band using a finite ground plane. Results from the simulation of the prototype with the finite plane show an excellent agreement with measurements. A final parametric study of the optimization variables is carried out. View full abstract»

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  • Domain Decomposition Method Based on Generalized Scattering Matrix for Installed Performance of Antennas on Aircraft

    Publication Year: 2007 , Page(s): 1833 - 1842
    Cited by:  Papers (22)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2112 KB) |  | HTML iconHTML  

    We describe the factorization (FACTOPO) domain decomposition method based on the boundary element method (BEM) and the finite element method (FEM) applied to the analysis of antenna performance on aircraft. The benefits of the subdomain method are mainly the ability to deal with collaborative studies involving several companies, and the reduction of the computation costs by one or more orders of magnitude, especially in the context of parametric studies. Furthermore, this paper proposes global functions defined on fictitious surfaces surrounding radiating elements, to deal with the computation of antenna far field patterns in a multidomain mode. By masking the complexity of the antenna (wires, thin surfaces, materials, feeding network) the external domain of the aircraft can be closed so that the combined field integral equation can be used, which is better conditioned than the electric field integral equation and converges much faster. The accuracy and efficiency of this technique is assessed by directivity computations of VHF monopole antennas mounted on Fokker 100 and ATR42 scaled mock-up. Domain decomposition results obtained by combining two sets of subdomains are compared with measurements and the FEKO commercial method of moments code. View full abstract»

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  • A Statistical Integral Equation Model for Shadow-Corrected EM Scattering From a Gaussian Rough Surface

    Publication Year: 2007 , Page(s): 1843 - 1855
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (894 KB) |  | HTML iconHTML  

    We propose a statistical model in conjunction with the integral equation formalism for electromagnetic scattering from Gaussian rough surfaces with small to moderate heights and Gaussian power spectra where we include the statistical features of the surface slopes and the effect of shadowing. In evaluating the Kirchoff incoherent power, for the correlated term due to correlation between the normal vectors of two neighboring points on the surface, an approximation scheme based on the decomposition of the covariance matrix is proposed. For the cross and complementary incoherent powers, due to their subdominant nature, the cross correlations between the surface slopes at different points on the surface are neglected to reduce the computational complexity. The validity of the proposed statistical integral equation model is demonstrated through agreement between its theoretical predictions and method of moment simulations. Moreover, all the simulated cases are outside the regions of validity of the small perturbation method and the conventional Kirchoff model, which indicates that the statistical model holds the potential of bridging the gap between these two traditional models. View full abstract»

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  • Numerical Methods for Solving the Problem of Electromagnetic Scattering by a Thin Finite Conducting Wire

    Publication Year: 2007 , Page(s): 1856 - 1861
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (567 KB) |  | HTML iconHTML  

    Scattering, absorption and extinction by a thin finite length conducting wire are computed numerically by solving the generalized Pocklington integro-differential equation using two approaches: the method of moments (MoM) with short range pulse basis functions via the point matching scheme and the Galerkin method with long range basis functions (Legendre polynomials modified to satisfy the boundary conditions of the problem). A new development included in the computations reported here involves a more accurate rendering of wires with lower aspect (length-to-diameter) ratios. Both methods converge to the same answer and satisfy the energy balance to within one percent. A comparison is made with an existing analytical theory by Waterman and Pedersen. This theory solves a more approximate form of the Pocklington equation and is found to have anomalies for some cases. The solutions of this paper agree with the analytical theory for very thin wires, and the results yield a small but significant amplitude and resonance shift for lower aspect ratios. All three solutions are in agreement with the numerous available experimental results to within the experimental errors. The numerical approaches provide a complete direct solution to the problem and remove all the anomalies which occurred in the analytical theory by Waterman and Pedersen. 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