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Antennas and Propagation, IEEE Transactions on

Issue 7 • Date July 2007

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Displaying Results 1 - 25 of 39
  • Table of contents

    Publication Year: 2007 , Page(s): C1 - 1901
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    Freely Available from IEEE
  • IEEE Transactions on Antennas and Propagation publication information

    Publication Year: 2007 , Page(s): C2
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  • Reactively Steered Ring Antenna Array for Automotive Application

    Publication Year: 2007 , Page(s): 1902 - 1908
    Cited by:  Papers (13)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (673 KB) |  | HTML iconHTML  

    A novel type of smart antenna, called a reactively steered ring antenna array (RSRAA), is proposed. The antenna features a conformal configuration with three overlapping one-wavelength ring elements. Directivity can be controlled by changing the values of variable reactance circuits that are embedded in the antenna. The antenna can be mounted on the windshield of an automobile without interfering with the view of the driver. An equivalent model of six dipole elements is derived from the original antenna configuration to enable simple calculation of directivity when a set of reactance values is given. The validity of the proposed equivalent model is confirmed by comparing simulation results calculated by the equivalent model and by the method of moments. Another simulation shows that the conventional reactance domain multiple signal classification algorithm can be applied to the proposed antenna while keeping the estimated direction-of-arrival number equal to the number of reactance circuits. In addition, the characteristics of an RSRAA, which is optimized at 2.4 GHz and is mounted on an automobile, are measured in an anechoic chamber, and directivity control is found to be implemented effectively. View full abstract»

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  • Analytical Model of the Split-Coaxial Balun and Its Application to a Linearly-Polarized Dipole or a CP Turnstile

    Publication Year: 2007 , Page(s): 1909 - 1918
    Cited by:  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1449 KB) |  | HTML iconHTML  

    A simple analytical transmission line model of a split-coaxial balun is proposed and tested. It is based on the coupled symmetric transmission line approach. The model leads to a closed-form analytical expression for the termination impedance/transfer function of the complete antenna system that includes antenna, balun, and a non-splitted coaxial line of certain length. It accepts the impedance of a center-fed symmetric antenna as input parameter. The model is in excellent agreement with full wave simulations and is confirmed by a series of prototype measurements. It can be applied to a linearly-polarized radiator or to a broadband circularly-polarized turnstile, where the phase quadrature is created by two complex-conjugate impedances. The present model only describes the impedance matching properties of the balun but is not capable of predicting the balance quality of baluns. View full abstract»

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  • Reconfigurable Multiband Antenna Designs for Wireless Communication Devices

    Publication Year: 2007 , Page(s): 1919 - 1928
    Cited by:  Papers (66)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1507 KB) |  | HTML iconHTML  

    New designs for compact reconfigurable antennas are introduced for mobile communication devices. The uniqueness of the antenna designs are that they allow various groups of their operating frequency bands to be selected electronically. In particular, each group of frequency bands, or mode, can be made to serve several different communication systems simultaneously. These systems may include various combinations of GSM, DCS, PCS, UMTS, Bluetooth, and wireless local-area network (LAN). Therefore, by electronically selecting different antenna modes, a variety of communication systems can be conveniently served by only one antenna. One advantage is that through the different operational modes, the total antenna volume can be reused, and therefore the overall antenna can be made compact. In these designs, the selection of the different modes is achieved by either i) switching different feeding locations of the antenna (switched feed) or ii) switching or breaking of the antenna's connection to the ground (switched ground). This paper demonstrates these two designs. For the first design of switched feed, it can support GSM, DCS, PCS, and UMTS. In the second design, the antenna makes use of a switched-ground technique, which can cover GSM, DCS, PCS, UMTS, Bluetooth, and 2.4 GHz wireless LAN. The designs are investigated when ideal switches and also various realistic active switches based on PIN diodes, GaAs field effect transistor, and MEMs configurations. The designs are verified through both numerical simulations and measurement of an experimental prototype. The results confirm good performance of the two multiband reconfigurable antenna designs. View full abstract»

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  • Wideband Circularly Polarized Dielectric Resonator Antenna

    Publication Year: 2007 , Page(s): 1929 - 1932
    Cited by:  Papers (17)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (844 KB) |  | HTML iconHTML  

    A circularly polarized quadruple strip feed cylindrical dielectric resonator antenna utilizing a pair of 90deg hybrid couplers is investigated experimentally. The antenna is shown to deliver an impedance bandwidth (S11 < -10 dB) of 34.5%, from 1.75 to 2.48 GHz, and an axial-ratio bandwidth (AR < 3 dB) of 25.9%, from 1.65 to 2.14 GHz. The gain and radiation patterns are found to be stable within the passband. View full abstract»

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  • Design of an Efficient X-Band Waveguide-Fed Microstrip Patch Array

    Publication Year: 2007 , Page(s): 1933 - 1939
    Cited by:  Papers (13)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (913 KB) |  | HTML iconHTML  

    The design and fabrication of a 10.5 GHz microstrip patch array fed by a waveguide is presented. The gain of this antenna is 29 dB and its efficiency is 65%. Commonly, the efficiency of conventional microstrip arrays at X-band is not more than 50%. This antenna demonstrates the ability to accomplish a very high efficiency at X-band in a simple structure. This is achieved by using a slotted waveguide to feed the planar array. To allow symmetrical feed of this antenna, the waveguide is a center-fed slotted waveguide, the two ends of which are shorted. The design procedure is expatiated, which contains the study and design of the waveguide-fed subarray structure and of the coax-to- waveguide transition structure. For designing this entire antenna, a three-dimensional electromagnetic field simulation software CST Microwave Studio is applied. Good agreement is achieved between measurement and simulation results. View full abstract»

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  • Direction of Arrival Estimation in the Presence of Noise Coupling in Antenna Arrays

    Publication Year: 2007 , Page(s): 1940 - 1947
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (708 KB) |  | HTML iconHTML  

    The direction of arrival (DOA) estimation problem in the presence of signal and noise coupling in antenna arrays is addressed. In many applications, such as smart antenna, radar and navigation systems, the noise coupling between different antenna array elements is often neglected in the antenna modeling and thus, may significantly degrade the system performance. Utilizing the exact noise covariance matrix enables to achieve high-performance source localization by taking into account the colored properties of the array noise. The noise covariance matrix of the antenna array consists of both the external noise sources from sky, ground and interference, and the internal noise sources from amplifiers and loads. Computation of the internal noise covariance matrix is implemented using the theory of noisy linear networks combined with the method of moments (MoM). Based on this noise statistical analysis, a new four-port antenna element consisting of two orthogonal loops is proposed with enhanced source localization performance. The maximum likelihood (ML) estimator and the Cramer-Rao lower bound (CRLB) for DOA estimation in the presence of noise coupling is derived. Simulation results show that the noise coupling in antenna arrays may substantially alter the source localization performance. The performance of a mismatched ML estimator based on a model which ignores the noise coupling shows significant performance degradation due to noise coupling. These results demonstrate the importance of the noise coupling modeling in the DOA estimation algorithms. View full abstract»

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  • A Dipole Excited Ultrawideband Dielectric Rod Antenna With Reflector

    Publication Year: 2007 , Page(s): 1948 - 1954
    Cited by:  Papers (12)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1729 KB) |  | HTML iconHTML  

    A novel very compact ultrawideband dielectric rod antenna with metallic reflector is presented. The desired HE11 mode on the rod is excited by a biconical dipole fed by a broadband tapered microstrip line balun. The input reflection remains below -10 dB from 3 up to 20 GHz. The antenna exhibits a flat gain larger than 7 dBi over the whole ultrawideband frequency range from 3 to 10 GHz approved by the Federal Communication Commission. An almost constant transient performance over a wide azimuth angle of plusmn40deg is obtained with small dispersion. View full abstract»

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  • A Varactor-Tunable High Impedance Surface With a Resistive-Lumped-Element Biasing Grid

    Publication Year: 2007 , Page(s): 1955 - 1962
    Cited by:  Papers (38)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2911 KB) |  | HTML iconHTML  

    A high impedance surface consisting of metallic square patches electrically connected through vias to the ground plane beneath them is made tunable. Tunability is achieved by connecting adjacent patches with varactor diodes thus altering the capacitance between the patches and hence the surface's resonance frequency. The varactor diodes are biased with the aid of a resistive grid. The grid is made resistive using surface mount resistors. Using an approximate equivalent circuit the effect of the varactor diode resistance is investigated for normal plane wave incidence. It is shown that at resonance, a small varactor resistance may lead to a significant absorption. The potential use of a waveguide simulator to characterize approximately the performance of the proposed metamaterial structure is investigated. View full abstract»

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  • A Robust Method for the Computation of Green's Functions in Stratified Media

    Publication Year: 2007 , Page(s): 1963 - 1969
    Cited by:  Papers (16)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (244 KB) |  | HTML iconHTML  

    Closed-form Green's functions for unbounded planar stratified media are derived in terms of cylindrical and spherical waves. The methodology is based on a two-level approximation of the spectral-domain representation of Green's functions. This robust, efficient, and fully numerical approach does not call for an analytical extraction of ldquoproblematicrdquo behaviors, such as the quasi-static terms and the surface wave poles, prior to the spectrum fitting. Instead, the spatial-domain Green's functions derived in this paper provide an accurate description of both the near-field singularity in the vicinity of the source and the far-field dominant behavior of the surface waves. View full abstract»

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  • An Efficient Volume Integral Equation Solution to EM Scattering by Complex Bodies With Inhomogeneous Bi-Isotropy

    Publication Year: 2007 , Page(s): 1970 - 1980
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (910 KB) |  | HTML iconHTML  

    A generalized volume integral equation method is formulated for electromagnetic scattering by arbitrarily shaped complex bodies with inhomogeneous bi-isotropy. Based on the volume equivalence principle, the integral equations are represented in terms of a pair of coupled bi-isotropic polarized volume electric and magnetic flux densities. Reduction of the integral equations into the corresponding matrix equations is obtained using the method of moments (MoM) combined with the tetrahedral mesh. In the MoM solution, the three-dimensional solenoidal function is incorporated as the basis function defined over each tetrahedral element and the details of implementation, particularly the treatment of integral singularities, will be elucidated. The efficiency and accuracy of the proposed method are validated by illustratively supported examples. View full abstract»

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  • A Three-Dimensional FDTD Subgridding Algorithm With Separated Temporal and Spatial Interfaces and Related Stability Analysis

    Publication Year: 2007 , Page(s): 1981 - 1990
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1407 KB) |  | HTML iconHTML  

    A finite-different time-domain subgrid algorithm locally refines the mesh at regions requiring higher resolution. A novel separation of spatial and temporal subgridding interfaces is presented that allows implementing a novel spatial subgridding method and investigating the stability of each subalgorithm individually. Details are given for a spatial subgridding algorithm having a 1:3 mesh ratio. In the spatial subgridding algorithm, the fine-mesh is constructed with a recessed interface and the interpolation scheme is designed to be symmetric to maintain the stability of the update process. The stability of the spatial subgridding algorithm is analyzed with a matrix method. Numerical examples showing stability and accuracy are provided. View full abstract»

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  • Analysis of Acousto-Electromagnetic Wave Interaction Using Sheet Boundary Conditions and the Finite-Difference Time-Domain Method

    Publication Year: 2007 , Page(s): 1991 - 1998
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (858 KB) |  | HTML iconHTML  

    Acousto-electromagnetic wave interaction occurs when an electromagnetic wave scatters from an object under seismic or acoustic illumination. The vibration of the object under acoustic excitation gives rise to a frequency modulated scattered field which depends on both the object and electromagnetic and acoustic source parameters. The objective of this study is to accurately calculate the Doppler spectrum of the bistatic scattered field which is usually orders of magnitude smaller than the fundamental component of the scattered field (the stationary target response). In this analysis the recently developed sheet boundary conditions are used to set up a duplicate problem of a stationary object having time varying sheet impedance and admittance accounting for the object vibration. The problem is formulated using the two-dimensional finite-difference time-domain (FDTD) method in an iterative scheme in order to find the broadband response of the scattered field Doppler component. Two-dimensional analytical solutions for a canonical geometry are used to verify the FDTD simulation results. View full abstract»

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  • Debye Function Expansions of Complex Permittivity Using a Hybrid Particle Swarm-Least Squares Optimization Approach

    Publication Year: 2007 , Page(s): 1999 - 2005
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (459 KB) |  | HTML iconHTML  

    With appropriate modifications, the finite-difference time-domain (FDTD) method can be used to analyze propagation through linear isotropic dispersive media. Although materials characterized by the Debye permittivity model can be analyzed accurately and efficiently using well established methods, the treatment of other types of frequency dependence is more difficult. This paper proposes the use of a weighted sum of Debye functions to approximate more general complex permittivity functions. A combination of the particle swarm optimization method and linear least squares optimization is used to find the relaxation frequencies and weights in the expansion, which can then be accommodated in the FDTD method using one of the established methods. Two key advantages of the proposed approach are that the relaxation frequencies are bandlimited and the weights are always positive. These two characteristics help to maintain the accuracy and stability of the FDTD solution. It is also shown that the correlation between the imaginary parts of two Debye functions is the same as that between the real parts. View full abstract»

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  • Periodic FDTD Analysis of a 2-D Leaky-Wave Planar Antenna Based on Dipole Frequency Selective Surfaces

    Publication Year: 2007 , Page(s): 2006 - 2012
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (711 KB) |  | HTML iconHTML  

    A periodic finite-difference time-domain (FDTD) analysis is presented and applied for the first time in the study of a two-dimensional (2D) leaky-wave planar antenna based on dipole frequency selective surfaces (FSSs). First, the effect of certain aspects of the FDTD modeling in the modal analysis of complex waves is studied in detail. Then, the FDTD model is used for the dispersion analysis of the antenna of interest. The calculated values of the leaky-wave attenuation constants suggest that, for an antenna of this type and moderate length, a significant amount of power reaches the edges of the antenna, and thus diffraction can play an important role. To test the validity of our dispersion analysis, measured radiation patterns of a fabricated prototype are presented and compared with those predicted by a leaky-wave approach based on the periodic FDTD results. View full abstract»

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  • Wavelet Based Deconvolution Algorithm for Time-Domain Near-Field ISAR Imaging

    Publication Year: 2007 , Page(s): 2013 - 2021
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2201 KB) |  | HTML iconHTML  

    Based on correlation receiver in communication theory, the measured backscattering waveform of a calibration conducting sphere is adopted as the system impulse response. This antenna-target system response is then approximated by the derivatives of a Gaussian function (DGF) as well as the Coiflets to restore the impulse response of the target and to reconstruct the ISAR images. Both the DGF and Coiflets are applied to the deconvolution and their results are compared. The Gaussian and Coiflet function parameters are derived by a best-fit to the measured time-domain system response. Employing the parametric fits, a lowpass filter has been automatically embedded which performs regularization of the conjugate gradient (CG) optimization and speeds up the CG convergence. Numerical results show that the image quality from the Coiflet system is similar to or better than from the DGF system. Owing to the continuity, smoothness, orthogonality and compact support of the Coiflets, the size of the system matrix has been reduced from 1024 times 1024 for DGF to 261 times 261, and the deconvolution process is accelerated more than 22 fold without sacrificing image characters. View full abstract»

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  • Predicting Antenna Noise Temperature Due to Rain Clouds at Microwave and Millimeter-Wave Frequencies

    Publication Year: 2007 , Page(s): 2022 - 2031
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1105 KB) |  | HTML iconHTML  

    Model-oriented methods to predict antenna noise temperature due to rainfall along slant paths are developed and illustrated for communication systems at Ka-band and above. The adopted Sky Noise Eddington Model (SNEM) relies on an accurate analytical solution of the radiative transfer equation and on stratiform and convective rainfall stratified structures, synthetically generated from cloud-resolving model statistics. The approach to predict antenna noise temperature is based on the multiple regression analysis, trained by SNEM-derived cloud radiative data sets, and can handle either slant-path attenuation or columnar liquid water or rain rate as input predictors. Statistical scaling with respect to frequency and zenith angle is also analyzed and modeled in the microwave and millimeter-wave range. In order to test the proposed prediction technique, measurements of the ITALSAT satellite ground-station at Pomezia (Rome, Italy) are taken into consideration for two case studies. Combined data from the ITALSAT three-beacon receiver at 18.7, 39.6, and 49.5 GHz and from a three-channel microwave radiometer at 13.0, 23.8, and 31.6 GHz are processed. Results are shown and discussed in terms of antenna noise temperature estimation by using the satellite-beacon path attenuation as predicting variable. View full abstract»

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  • Electromagnetic Wave Propagation Through Chaff Clouds

    Publication Year: 2007 , Page(s): 2032 - 2042
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (748 KB) |  | HTML iconHTML  

    The computation of electromagnetic wave scattering by clouds of dipoles is straightforward when the dipole density is small. For higher density clouds, the coupling effects between the dipoles and their attenuation effects on the wave must be considered. This is accomplished herein by replacing the randomly distributed dipoles in the cloud by a conducting continuum. The conductivity of this continuum is determined by requiring that the radar cross section (RCS) of an infinitesimally thin slab of the continuum be the same as that of a similar portion of the dipole cloud. The thinness of this reference dipole cloud eliminates the necessity to consider inter-dipole coupling. The reflection and transmission characteristics of the cloud are then obtained using standard methods for propagation through the effective conductor. RCS results are shown to agree with coupled numerical integral equation solutions for scattering from a closely spaced system of wires. Simple formulas are derived for the attenuation effects of the dipole cloud. For most cases of interest, the wave with wave length lambda attenuates through a cloud of half wave dipoles of density p at the rate of 0.655 (plambda3) dB per lambda. View full abstract»

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  • Adjacent Satellite Interference Effects on the Outage Performance of a Dual Polarized Triple Site Diversity Scheme

    Publication Year: 2007 , Page(s): 2043 - 2055
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (739 KB) |  | HTML iconHTML  

    The design of reliable, modern satellite communication networks, in which both frequency and orbital congestion are increasing, requires modeling of interference effects. The dominant sources of aggravation of nominal interference due to propagation phenomena are assumed to be differential rain attenuation from an adjacent satellite communication network operating at the same frequency and cross polarization due to rain and ice-crystals. A physical methodology to predict the statistics of the carrier-to-noise-plus-total-interference (CNIDR), which has already been applied to single and double-site systems, is extended to include triple-site diversity reception schemes. This method is based on a model of convective raincells model and the lognormal assumption for both the point rainfall statistics and slant path rain attenuation. The statistical properties of spatial inhomogeneity of rain attenuation over six satellite slant paths is firstly here presented. A set of simple, approximate formulas are presented which follow from a regression analysis on the previous theoretical results. The results serve to examine the influence of various parameters upon the total availability performance. View full abstract»

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  • Observation Site Atmospheric Phase Fluctuations Observed by Three-Element VLBI

    Publication Year: 2007 , Page(s): 2056 - 2063
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2045 KB) |  | HTML iconHTML  

    The beacon signals from a geostationary satellite were observed using three-element very long baseline interferometry (VLBI), and the phase fluctuations along the baselines between three sites were obtained. The atmospheric phase fluctuations at each observation site were derived from the baseline phase fluctuation data. The fluctuations were classified into three time-interval regions based on the dependence of the Allan standard deviation of the fluctuations on the time interval. In the region where the interval was less than a few seconds and in the one where it was greater than one hundred seconds, the curve of the Allan standard deviation was steep and showed the property of white phase noise. In the region between these two regions, the dependence of the Allan standard deviation on the time interval was weak. The magnitude of the Allan standard deviations for the three observation sites showed time variations in the region where the time interval was longer than a few seconds. Comparison with the weather conditions suggested that the time variations of the Allan standard deviation reflected atmospheric instability above the sites. View full abstract»

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  • Radar-Target Identification via Exponential Extinction-Pulse Synthesis

    Publication Year: 2007 , Page(s): 2064 - 2072
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (926 KB) |  | HTML iconHTML  

    New contributions to noncooperative radar-target discrimination using only the scattered response of conductive objects are presented in this paper. The technique studied is the extinction-pulse (E-pulse), which makes use of natural resonances as discrimination features. The E-pulse expansion using complex exponential functions as basis functions is proposed, obtaining new E-pulses with characteristics completely different from those in the literature. Specifically, a weighting factor is added to modulate the exponential frequency, providing E-pulses with better discrimination capability. Numerical results achieved in the discrimination between thin straight wires of different lengths show that the proposed exponential E-pulses improve the discrimination results with respect to other types of E-pulses in the literature. View full abstract»

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  • AIM Analysis of Electromagnetic Scattering by Arbitrarily Shaped Magnetodielectric Object

    Publication Year: 2007 , Page(s): 2073 - 2079
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (752 KB) |  | HTML iconHTML  

    A fast solution to the electromagnetic scattering by large-scale three-dimensional magnetodielectric objects with arbitrary permittivity and permeability is presented. The scattering problem is characterized by using coupled field volume integral equation (CF-VIE). By considering the total electric and magnetic fields, i.e., the sum of incident fields and the radiated fields by equivalent electric and magnetic volume currents, the CF-VIE can be established in the volume of the scatterers. The resultant CF-VIE is discretized and solved by using the method of moments (MoM). For large-scale scattering problems, the adaptive integral method (AIM) is then applied in the MoM in order to reduce the memory requirement and accelerate the matrix-vector multiplication in the iterative solver. The conventional AIM has been modified to cope with the two sets of equivalent volume currents. View full abstract»

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  • Electric Field Distributions of Wearable Devices Using the Human Body as a Transmission Channel

    Publication Year: 2007 , Page(s): 2080 - 2087
    Cited by:  Papers (37)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2034 KB) |  | HTML iconHTML  

    Recently, wearable devices which use the human body as a transmission channel have been developed. However, there has been a lack of information related to the transmission mechanism of such devices in the physical layer. Electromagnetic communication trials using the human body as a transmission medium have more than a decade's history. However, most of the researches have been conducted by researchers who just want to utilize the fact and practically no physical mechanisms have been researched until recently. Hence, in this paper, the authors propose some calculation models of the human body equipped with the wearable devices by using the finite difference time domain (FDTD) method. Moreover, a biological tissue-equivalent solid phantom is utilized to show the validity of the calculation. From these investigations, the authors determine the transmission mechanism of the wearable devices using the human body as a transmission channel. View full abstract»

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  • A Novel Dual-Band Printed Diversity Antenna for Mobile Terminals

    Publication Year: 2007 , Page(s): 2088 - 2096
    Cited by:  Papers (59)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1695 KB) |  | HTML iconHTML  

    A novel dual-band printed diversity antenna is proposed and studied. The antenna, which consists of two back-to- back monopoles with symmetric configuration, is printed on a printed circuit board. The effects of some important parameters of the proposed antenna are deeply studied and the design methodology is given. A prototype of the proposed antenna operating at UMTS (1920-2170 MHz) and 2.4-GHz WLAN (2400-2484 MHz) bands is provided to demonstrate the usability of the methodology in dual-band diversity antenna for mobile terminals. In the above two bands, the isolations of the prototype are larger than 13 dB and 16 dB, respectively. The measured radiation patterns of the two monopoles in general cover complementary space regions. The diversity performance is also evaluated by calculating the envelope correlation coefficient, the mean effective gains of the antenna elements and the diversity gain. It is proved that the proposed antenna can provide spatial and pattern diversity to combat multipath fading. 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