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# IEEE Transactions on Antennas and Propagation

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Displaying Results 1 - 25 of 51

Publication Year: 2010, Page(s):C1 - 3105
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• ### IEEE Transactions on Antennas and Propagation publication information

Publication Year: 2010, Page(s): C2
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• ### Design of Frequency Reconfigurable Antennas Using the Theory of Network Characteristic Modes

Publication Year: 2010, Page(s):3106 - 3113
Cited by:  Papers (19)
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This paper demonstrates a design procedure for frequency tunable reconfigurable antennas based on the application of reactive loads. Unlike other design procedures, antennas of arbitrary geometry can be tuned utilizing the proposed design framework. The design technique utilizes the theory of network characteristic modes to systematically compute reactive load values required to resonate any anten... View full abstract»

• ### Lower Bounds on the Q of Electrically Small Dipole Antennas

Publication Year: 2010, Page(s):3114 - 3121
Cited by:  Papers (52)
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General expressions are obtained for the lower bounds on the quality factor (Q) of electrically small electric- and magnetic-dipole antennas confined to an arbitrarily shaped volume V and excited by general sources or by global electric-current sources alone. The lower-bound expressions depend only on the direction of the dipole moment with respect to V , the electrical size of V , and the static ... View full abstract»

• ### Analysis and Design of a Differentially-Fed Frequency Agile Microstrip Patch Antenna

Publication Year: 2010, Page(s):3122 - 3130
Cited by:  Papers (37)
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The design of a frequency agile microstrip patch antenna is described that is readily interfaced with differential RF transceivers. By integrating three pairs of varactor diodes with the patch antenna, and tuning them in unison, frequency tuning ratios approaching 2 are possible with the design. This is made possible by the intrinsically broadband nature of the differential feeding scheme used. An... View full abstract»

• ### Coplanar Capacitively Coupled Probe Fed Microstrip Antennas for Wideband Applications

Publication Year: 2010, Page(s):3131 - 3138
Cited by:  Papers (22)
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The design and analysis of a coplanar capacitive fed microstrip antenna suspended above the ground plane is presented. It is demonstrated that the proposed approach can be used for designing antennas with impedance bandwidth of about 50% and a good gain to operate in various microwave bands. The model of the antenna incorporates the capacitive feed strip which is fed by a coaxial probe using equiv... View full abstract»

• ### Theory of Electromagnetic Time-Reversal Mirrors

Publication Year: 2010, Page(s):3139 - 3149
Cited by:  Papers (40)  |  Patents (1)
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The theory of monochromatic time-reversal mirrors (TRM) or equivalently phase conjugate mirrors is developed for electromagnetic waves. We start from the fundamental time-symmetry of the Maxwell's equations. From this symmetry, a differential expression similar to the Lorentz reciprocity theorem is deduced. The radiating conditions on TRM are expressed in terms of 6-dimension Green's functions. To... View full abstract»

• ### Microstrip-Fed Wideband Circularly Polarized Printed Antenna

Publication Year: 2010, Page(s):3150 - 3156
Cited by:  Papers (26)
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A wideband circularly-polarized printed antenna is proposed, which employs an asymmetrical dipole and a slit in the ground plane which are fed by an L-shaped microstrip feedline using a via. The proposed antenna geometry is arranged so that the orthogonal surface currents, which are generated in the dipole, feedline and ground plane, have the appropriate phase to provide circular polarization. A p... View full abstract»

• ### Wideband and High-Gain Composite Cavity-Backed Crossed Triangular Bowtie Dipoles for Circularly Polarized Radiation

Publication Year: 2010, Page(s):3157 - 3164
Cited by:  Papers (43)
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A composite cavity-backed antenna excited by crossed triangular bowtie dipoles is proposed and investigated for circular polarization (CP) applications. It is fed by a novel balun, i.e., a transition from a microstrip line to double slot lines, providing symmetrical electric field distributions at the feeding port. Measurements of an optimized antenna prototype show that it can achieve an impedanc... View full abstract»

• ### Low-Profile Leaky Wave Electric Monopole Loop Antenna Using the $beta=0$ Regime of a Ferrite-Loaded Open Waveguide

Publication Year: 2010, Page(s):3165 - 3174
Cited by:  Papers (9)
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A novel low-profile leaky-wave electric monopole loop antenna in the regime of a composite right/left-handed (CRLH) ferrite-loaded open waveguide is presented. Despite its closed configuration, this structure supports a traveling-wave mode due to its non-reciprocity. Moreover, this mode exhibits an infinite wavelength in the regime, achieved at the transition frequency between the backward and for... View full abstract»

• ### Ultrawideband Hemispherical Helical Antennas

Publication Year: 2010, Page(s):3175 - 3181
Cited by:  Papers (7)
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A compact ultrawideband antenna with hemispherical helical geometry is proposed and investigated both theoretically and experimentally. The radiating element of this antenna consists of a tapered metallic strip that assumes a non-conformal orientation relative to the hemispherical surface in order to yield maximum bandwidth. The number of turns is about four and half with a constant spacing betwee... View full abstract»

• ### Transmitter and Receiver Isolation by Concentric Antenna Structure

Publication Year: 2010, Page(s):3182 - 3188
Cited by:  Papers (6)
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A concentric antenna structure with transmitter (Tx) and receiver (Rx) isolation characteristic is proposed. For both cases that Tx and Rx use the same frequency or different frequencies, Tx leakage can be removed by the proposed antenna structure. The field couplings between antennas are mathematically presented and Tx leakage cancellation is theoretically examined. To theoretically verify the ca... View full abstract»

• ### True-Time-Delay Beamforming With a Rotman-Lens for Ultrawideband Antenna Systems

Publication Year: 2010, Page(s):3189 - 3195
Cited by:  Papers (16)  |  Patents (1)
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An analytical design model for Rotman-lenses is presented, with an accurate treatment of the return loss of the ports and their phase centers. The detailed design equations allow a very fast prototyping prior to numerical simulations for the final adjustment. Based on the presented model a prototype has been built for the true-time-delay phasing of an antenna array for the ultrawideband frequency ... View full abstract»

• ### Frequency Agile Switched Beam Antenna Array System

Publication Year: 2010, Page(s):3196 - 3204
Cited by:  Papers (11)
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A dual frequency reconfigurable antenna array and its associated phase shifter are presented. The system is capable of operation at two independent frequencies (4.7 GHz and 7.5 GHz) while switching between four different radiation patterns pointing at different spatial locations for each frequency. The reconfigurability is achieved by using high performance PIN diodes acting as microwave switches. View full abstract»

• ### A Measurement System for the Complex Far-Field of Physically Large Antenna Arrays Under Noisy Conditions Utilizing the Equivalent Electric Current Method

Publication Year: 2010, Page(s):3205 - 3211
Cited by:  Papers (5)
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Precipitation in the form of snow or rain could severely degrade the performance of large antenna arrays, in particular if knowledge about the beam shape and pointing direction in absolute numbers is necessary. In this paper, a method of estimating the far-field of each individual antenna element using the equivalent electric current approach is presented. Both a least squares estimator and a Kalm... View full abstract»

• ### Scalar and Tensor Holographic Artificial Impedance Surfaces

Publication Year: 2010, Page(s):3212 - 3221
Cited by:  Papers (185)  |  Patents (7)
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We have developed a method for controlling electromagnetic surface wave propagation and radiation from complex metallic shapes. The object is covered with an artificial impedance surface that is implemented as an array of sub-wavelength metallic patches on a grounded dielectric substrate. We pattern the effective impedance over the surface by varying the size of the metallic patches. Using a holog... View full abstract»

• ### Reflections From Multiple Surfaces Without Edges

Publication Year: 2010, Page(s):3222 - 3230
Cited by:  Papers (3)
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An algorithm is presented for calculating the positions of the specular points that appear when a collection of reflecting surfaces is illuminated by an external source. The set of specular points is represented as the fixed point of a certain mapping, and this fixed point is calculated by the method of successive approximations (MSA). The MSA is an iterative technique which is essentially differe... View full abstract»

• ### On the Convergence of the Eigencurrent Expansion Method Applied to Linear Embedding via Green's Operators (LEGO)

Publication Year: 2010, Page(s):3231 - 3238
Cited by:  Papers (7)
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The scattering from a large complex structure comprised of many objects may be efficiently tackled by embedding each object within a bounded domain (brick) which is described through a scattering operator. Upon electromagnetically combining the scattering operators we arrive at an equation which involves the total inverse scattering operator S-1 of the structure: We call this procedure ... View full abstract»

• ### Unified Time- and Frequency-Domain Approach for Accurate Modeling of Electromagnetic Radiation Processes in Ultrawideband Antennas

Publication Year: 2010, Page(s):3239 - 3255
Cited by:  Papers (9)
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A singularity-expansion-method-based methodology is proposed for the accurate time- and frequency-domain analysis and modeling of wave radiation processes in ultrawideband antennas. By means of this approach, the transient electromagnetic field distribution in the Fraunhofer region is presented in analytical closed form as the superposition of outgoing propagating non-uniform spherical waves. The ... View full abstract»

• ### Enhanced A-EFIE With Perturbation Method

Publication Year: 2010, Page(s):3256 - 3264
Cited by:  Papers (36)
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The recently developed augmented electric field integral equation (A-EFIE) remedies the well-known low-frequency breakdown. However, it loses accuracy of current when applied to certain low-frequency applications like plane wave scattering. This paper addresses the low-frequency inaccuracy problem, and proposes a perturbation method as a remedy. A-EFIE with perturbation solves the same A-EFIE matr... View full abstract»

• ### Exponentially Converging Nystrom Methods in Scattering From Infinite Curved Smooth Strips— Part 1: TM-Case

Publication Year: 2010, Page(s):3265 - 3274
Cited by:  Papers (11)
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Low-order subdomain basis methods of moments provide little help when highly accurate electromagnetic computations are required. High order modeling, on the other hand, can fill the need for enhanced accuracy but at the expense of greater implementation cost. To supplement such methods, this paper presents Nyström techniques, both easily implemented and highly accurate, relevant to TM scat... View full abstract»

• ### Exponentially Converging Nystrom Methods in Scattering From Infinite Curved Smooth Strips— Part 2: TE-Case

Publication Year: 2010, Page(s):3275 - 3281
Cited by:  Papers (12)
| | PDF (296 KB) | HTML

Low-order subdomain basis methods of moments provide little help when highly accurate electromagnetic computations are required. High order modeling, on the other hand, can fill the need for enhanced accuracy but at the expense of greater implementation cost. To supplement such methods, this paper presents Nyström techniques, both easily implemented and highly accurate, relevant to TE scat... View full abstract»

• ### Frequency-Dependent FDTD Simulation of the Interaction of Microwaves With Rocket-Plume

Publication Year: 2010, Page(s):3282 - 3288
Cited by:  Papers (8)
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The ionized exhaust plumes of solid rocket motors may interfere with RF transmission under certain flight conditions. To understand the important physical processes involved, we measured microwave attenuation and phase delay due to the exhaust plume during sea-level static firing tests for a full-scale solid propellant rocket motor. The measured data were compared with the results of a detailed si... View full abstract»

• ### Two-Dimensional Microwave Imaging Based on Hybrid Scatterer Representation and Differential Evolution

Publication Year: 2010, Page(s):3289 - 3298
Cited by:  Papers (26)
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A hybrid method for solving two-dimensional inverse scattering problems is proposed. The method utilizes differential evolution as a global optimizer and is based on two alternative representations of the unknown scatterer. Initially, the scatterer properties are represented by means of truncated cosine Fourier series expansion that involves limited number of unknown expansion coefficients. Then, ... View full abstract»

• ### Scattering by an Infinite Dielectric Cylinder Having an Elliptic Metal Core: Asymptotic Solutions

Publication Year: 2010, Page(s):3299 - 3309
Cited by:  Papers (4)
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The scattering of a plane electromagnetic wave by an infinite circular dielectric cylinder, containing an elliptic metallic one is considered in this work. The electromagnetic field is expressed in terms of both circular and elliptical-cylindrical wave functions, connected with one another by well-known expansion formulas. When the solution is specialized to small values of the parameter h = c/a, ... View full abstract»

## Aims & Scope

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

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## Meet Our Editors

Editor-in-Chief                                             Danilo Erricolo