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Antennas and Propagation, IEEE Transactions on

Issue 12 • Date Dec. 2012

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  • Table of Contents

    Publication Year: 2012 , Page(s): C1 - 5506
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  • IEEE Transactions on Antennas and Propagation publication information

    Publication Year: 2012 , Page(s): C2
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  • 2012 Distinguished Achievement Award

    Publication Year: 2012 , Page(s): 5507
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  • 2012 Chen-To Tai Distinguished Educator Award

    Publication Year: 2012 , Page(s): 5508
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  • 2012 John Kraus Antenna Award

    Publication Year: 2012 , Page(s): 5509
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  • 2012 Donald G. Dudley Jr. Undergraduate Teaching Award

    Publication Year: 2012 , Page(s): 5510
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  • 2012 R.W.P. King Award

    Publication Year: 2012 , Page(s): 5511
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  • 2012 Harold A. Wheeler Applications Prize Paper Award

    Publication Year: 2012 , Page(s): 5512 - 5514
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  • 2012 Sergei A. Schelkunoff Transactions Prize Paper Award

    Publication Year: 2012 , Page(s): 5515 - 5516
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  • 2012 Piergiorgio L.E. Uslenghi Letters Prize Paper Award

    Publication Year: 2012 , Page(s): 5517 - 5518
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  • 2012 IEEE Antennas and Propagation Edward E. Altshuler Prize Paper

    Publication Year: 2012 , Page(s): 5519 - 5520
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  • 2012 IEEE Fellow Awards From the Antennas and Propagation Society

    Publication Year: 2012 , Page(s): 5521
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  • Low-Dispersion Spiral Antennas

    Publication Year: 2012 , Page(s): 5522 - 5530
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2255 KB) |  | HTML iconHTML  

    A two-arm power spiral antenna with inherently low dispersion is proposed. Analytical, computational, and experimental steps are taken to demonstrate its superior time domain performance. When compared with conventional Archimedean and equiangular spirals, up to 40% improved fidelity factor and pulse compression are achieved. It is, however also shown that the power spiral's mid and high band axial ratio is compromised. To enhance the power spiral's frequency domain characteristics, a combined Archimedean/power spiral is developed. VSWR below 2:1, clean patterns with wobble on the wave (WoW) and axial ratio <; 3 dB over multi-octave wide bandwidth, all similar to those of well-performed frequency domain spirals, and more than 34% fidelity factor improvement over the wide-field of view are achieved. Herein presented results show that the proposed spiral topology can have simultaneously good frequency and time domain characteristics and no additional hardware or software is needed to enhance either. View full abstract»

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  • A Radial Line Slot Antenna for an Elliptical Beam

    Publication Year: 2012 , Page(s): 5531 - 5537
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1580 KB) |  | HTML iconHTML  

    A radial line slot antenna (RLSA) with a quasi-elliptical aperture to create an elliptical beam is discussed in this paper. A simple feeding structure consisting of a coaxial feeder and two parasitic pins is designed to produce the feed pattern required for uniform illumination over the aperture. The slot length distribution in the radial direction is designed to be similar to conventional RLSAs for specified radial dimensions associated with the elliptical aperture. A 22 GHz quasi-elliptical RLSA with major and minor axes of 300 mm and 150 mm, respectively, was designed. The radiation pattern predicted by a method of moments (MoM) had 3 dB beam-widths of 2.46 and 4.9 degrees in the 0- and 90-degree cut-planes, and the directivity of 33 dBi corresponds to an aperture efficiency of 71.5%. The measured 3 dB beam-widths and the directivity agree well with the predictions. The measured antenna gain of 31.8 dB at 22.0 GHz corresponds to an antenna efficiency of 56%, while the axial ratio is 1.74 dB. View full abstract»

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  • Automatic Design of CP-RLSA Antennas

    Publication Year: 2012 , Page(s): 5538 - 5547
    Cited by:  Papers (15)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2520 KB) |  | HTML iconHTML  

    In this paper a procedure is presented, allowing the automatic design of circular polarized radial line slot antennas, with either pencil or shaped beam patterns. The antenna slot layout is refined by an optimization scheme based on the physical picture behind the working mechanism of the array. The validity of the approach has been proved by designing very efficient pencil beam antennas, either with maximum directivity or with controlled side lobe levels, and a shaped isoflux beam antenna. View full abstract»

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  • Gain Enhancement of H-Plane Sectoral Post-Wall Horn Antenna by Connecting Tapered Slots for Millimeter-Wave Communication

    Publication Year: 2012 , Page(s): 5548 - 5556
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1998 KB) |  | HTML iconHTML  

    We propose a millimeter-wave antenna to serve as an element antenna for a multi-sector switched-beam antenna, which can be fed by a post-wall waveguide. Several tapered slot antennas are connected to an aperture of an H-plane sectoral post-wall horn antenna whose radiation pattern is narrowed in the H-plane to further narrow the pattern in the E-plane. Moreover, the aperture of each tapered slot antenna is loaded with a dielectric to increase the gain. We designed an antenna whose gain is over 16 dBi in the frequency band of 57-66 GHz. The wideband property is experimentally examined. View full abstract»

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  • Terahertz Horn Antenna Based on Hollow-Core Electromagnetic Crystal (EMXT) Structure

    Publication Year: 2012 , Page(s): 5557 - 5563
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1421 KB) |  | HTML iconHTML  

    An all-dielectric terahertz (THz) horn antenna based on hollow-core electromagnetic crystal structure is designed, fabricated and characterized. Simulation shows that the antenna works above 100 GHz, with better than 30 dB return loss and highly directional radiation pattern. Fabrication of the antenna is done using a THz polymer-jetting rapid prototyping technique. Characterization of the antenna is performed using a THz time-domain spectrometer. Measurement results of the far-field radiation patterns show good agreement with simulation results. View full abstract»

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  • A Novel Wideband Circularly Polarized Printed Antenna

    Publication Year: 2012 , Page(s): 5564 - 5570
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1345 KB) |  | HTML iconHTML  

    A circularly polarized printed antenna, capable of operating over an octave bandwidth is designed and fabricated. The design is evolved from classical printed monopole/dipole geometry. It employs a microstrip-line fed rectangular radiator, printed on the top of a substrate. The ground, extended as another rectangular radiator is printed on the bottom of the substrate. Both the top and bottom radiators are asymmetrically configured in such a way that the surface currents on them are orthogonal so as to produce left-hand circular polarization (LHCP). The antenna configuration is simulated using a commercially available EM solver. The simulated and measured results closely match within the operating bandwidth. The measured results show a -10-dB return loss bandwidth of 800 MHz to 4.15 GHz and a 3-dB axial ratio bandwidth of 1.5 GHz to 3.4 GHz. For the designed center frequency of 2.45 GHz, these correspond to 136% and 77% respectively. A parametric study of the design is carried out and the mechanism of circular polarization is described. View full abstract»

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  • Compact Broadband Dual Coupling-Feed Circularly Polarized RFID Microstrip Tag Antenna Mountable on Metallic Surface

    Publication Year: 2012 , Page(s): 5571 - 5577
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1428 KB) |  | HTML iconHTML  

    A square-shaped microstrip RFID tag antenna designed for 915 MHz band is proposed. The antenna is capacitively excited by a dual-offset coupling feed network with one of the feed lines a quarter-wavelength longer than the other. By selecting appropriate dimensions for the coupled lines and feed-lines, along with desirable coupling distance between the coupled line and square patch, the input impedance of the proposed tag antenna can be easily controlled, which results in excellent impedance matching. Moreover, by incorporating the dual-offset feed technique with the method of embedding a cross slot of unequal arm lengths into the square patch, the bandwidth of the circularly polarized (CP) operation can be enhanced. The measured 6-dB return-loss bandwidth of the tag antenna is 25 MHz (902-927 MHz), and its corresponding 3-dB axial-ratio (AR) bandwidth is 20 MHz (903-923 MHz). Further experimental results show that the proposed tag antenna can provide slightly better reading range and gain when mounted on a large metallic surface. View full abstract»

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  • Design Optimization of a Low-Profile UWB Body-of-Revolution Monopole Antenna

    Publication Year: 2012 , Page(s): 5578 - 5586
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2182 KB) |  | HTML iconHTML  

    This paper presents a systematic design approach for low-profile UWB body-of-revolution (BoR) monopole antennas with specified radiation objectives and size constraints. The proposed method combines a random walk scheme, the genetic algorithm, and a BoR moment method analysis for antenna shape optimization. A weighted global cost function, which minimizes the difference between potential optimal points and a utopia point (optimal design combining 3 different objectives) within the criterion space, is adapted. A 24'' wide and 6'' tall aperture was designed operating from low VHF frequencies up to 2 GHz. This optimized antenna shape reaches -15 dBi gain at 41 MHz on a ground plane and is only λ/12 in aperture width and λ/50 in height at this frequency. The same antenna achieves VSWR <; 3 from 210 MHz up to at least 2 GHz. Concurrently, it maintains a realized gain of ~5 dBi with moderate oscillations across the band of interest. A resistive treatment was further applied at the top antenna rim to improve matching and pattern stability. Measurements are provided for validation of the design. Of importance is that the optimized aperture delivers a larger impedance bandwidth as well as more uniform gain and pattern when compared to a previously published inverted-hat antenna of the same size. View full abstract»

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  • Differentially Fed Dual-Band Implantable Antenna for Biomedical Applications

    Publication Year: 2012 , Page(s): 5587 - 5595
    Cited by:  Papers (12)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1957 KB) |  | HTML iconHTML  

    A novel differentially fed dual-band implantable antenna is proposed for the first time for a fully implantable neuro-microsystem. The antenna operates at two center frequencies of 433.9 MHz and 542.4 MHz, which are close to the 402-405 MHz medical implant communication services (MICS) band, to support sub-GHz wideband communication for high-data rate implantable neural recording application. The size of the antenna is 480.06 mm3 (27 mm × 14 mm × 1.27 mm). The simulated and measured bandwidths are 7.3% and 7.9% at the first resonant frequency, 5.4% and 6.4% at the second resonant frequency. The specific absorption rate (SAR) distribution induced by the implantable antenna inside a tissue-mimicking solution is evaluated. The performance of the communication link between the implanted antenna and external half-wavelength dual-band dipole is also examined. View full abstract»

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  • A Mode-Based Design Method for Dual-Band and Self-Diplexing Antennas Using Double T-Stubs Loaded Aperture

    Publication Year: 2012 , Page(s): 5596 - 5603
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1673 KB) |  | HTML iconHTML  

    A mode-based design method for dual-band and self-deplexing antennas is presented. By analyzing the E-field distributions and cut-off frequencies of the individual modes in a T-stub loaded aperture, we selected two proper modes for the antenna designed for dual-frequency operations. The desired feature is that at the two different frequencies, the antenna may perform the same or similar radiation characteristics including the polarization, the pattern shape, and the gain level. A rectangular aperture loaded with double T-stubs was employed for the illustration basis. The proposed method was demonstrated to the dual-band antenna and self-diplexing antenna design with promising performances. The presented dual-band antenna performed a wide range of the frequency ratio from 1.3 to 3.0 under a fixed antenna size. The proposed self-diplexing antenna achieved good port isolation better than 26 dB in both operating bands. Both illustrated antenna designs were successfully verified with built prototypes of which the simulation and measurement results were quite consistent. View full abstract»

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  • Design of Multi-Frequency Compact Antennas for Automotive Communications

    Publication Year: 2012 , Page(s): 5604 - 5612
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2286 KB) |  | HTML iconHTML  

    Two designs of multi-band antennas for automotive communications are presented. Both antennas are designed to operate in four frequency bands (GSM, E-GSM, DCS, PCS) and are intended to be integrated in a PCB, placed inside a plastic box and mounted under the dashboard of the vehicle. The first design is a planar printed antenna fully integrated into the printed circuit board (PCB), thus reducing the cost virtually to zero; the second design is a three dimensional antenna, which does not require any dedicated space on the PCB. Both antennas have been designed taking into account the presence of the other electronic components on the PCB. The simulated reflection coefficients and radiation patterns of both antennas are in good agreement with prototype measurements. View full abstract»

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  • Multiband Compact Printed Dipole Antennas Using NRI-TL Metamaterial Loading

    Publication Year: 2012 , Page(s): 5613 - 5626
    Cited by:  Papers (12)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3008 KB) |  | HTML iconHTML  

    A compact, fully-printed negative-refractive-index transmission-line (NRI-TL) metamaterial-loaded dipole antenna is proposed, which exhibits multiband resonant characteristics that are not harmonically related. The multiband behavior is achieved by loading a host dipole antenna with series capacitive gaps and shunt inductive strips, to form a two unit-cell NRI-TL loaded antenna. By modeling the right-handed dipole sections as biconical transmission lines, the rich dispersion properties of the NRI-TL structure can be exploited, while still creating an effective radiator. An equivalent circuit model of the NRI-TL antenna is developed, and it is shown that its performance agrees well with the results obtained using full-wave simulations. It is also shown that the resonant behavior of the antenna can be adjusted by changing its geometrical parameters, which in turn tune the loading parameters of each NRI-TL unit cell. As such, both dual-band and triband versions of the antenna are designed and fabricated. The dual-band version exhibits three distinct resonances at 1.15, 2.88, and 3.72 GHz, with measured -10 dB bandwidths of 37 and 1150 MHz. The lowest resonance at 1.15 GHz corresponds to a 47% reduction in the resonant frequency compared to that of a reference unloaded dipole antenna, which translates into a size miniaturization factor of approximately two. The antenna exhibits stable dipolar radiation patterns with a linear electric field polarization, and has a total size of 50 × 10 × 0.79 mm3 or 0.19λ0 × 0.04λ0 × 0.003λ0 at 1.15 GHz. Throughout the operating bands the measured gain and radiation efficiency vary from 0.11 to 3.26 dBi and 49.5% to 95.6%, respectively. View full abstract»

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  • Square Ring Antenna With Reconfigurable Patch Using Shape Memory Alloy Actuation

    Publication Year: 2012 , Page(s): 5627 - 5634
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1455 KB) |  | HTML iconHTML  

    A pattern reconfigurable ring-patch antenna is presented. It comprises a bendable parasitic plate located in the middle of a fixed square ring. The fixed ring supports the feed, and the plate is effectively a parasitic structure. The plate's bending action is from a bisecting hinge between the rectangular halves (flaps) that can be actuated separately. The actuation is by extending a shape memory alloy spring. The restoration is by decompressing the shape memory spring action using a parallel standard spring. The parasitic plate thus reconfigures with rectangular flaps which bend up, level, and down, relative to the ring plane. As a result of the reconfiguration, the pattern of the antenna is changed while the impedance match is maintained. Simulated and experimental results are presented for the pattern and impedance of a 100 mm × 100 mm square ring patch antenna prototype operating at 1.15 GHz. The effects of some geometric parameters on the pattern and impedance are investigated in order to analyze the pattern changing mechanism. A two-element array of the reconfigurable ring-patch antenna is presented that provides further de-correlation of the patterns. View full abstract»

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Aims & Scope

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

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Editor-in-Chief                                                 Kwok W. Leung