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Antennas and Propagation, IEEE Transactions on

Issue 12 • Date Dec. 2009

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  • Table of contents

    Publication Year: 2009 , Page(s): C1 - 3705
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  • IEEE Transactions on Antennas and Propagation publication information

    Publication Year: 2009 , Page(s): C2
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  • 2009 Antennas and Propagation Society Awards 2009 Distinguished Achievement Award Recipient

    Publication Year: 2009 , Page(s): 3706
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  • 2009 Chen-To Tai Distinguished Educator Award

    Publication Year: 2009 , Page(s): 3707
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  • 2009 John Kraus Antenna Award

    Publication Year: 2009 , Page(s): 3708
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  • 2009 Donald G. Dudley, Jr. Undergraduate Teaching Award

    Publication Year: 2009 , Page(s): 3709
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  • 2009 R.W.P. King Award

    Publication Year: 2009 , Page(s): 3710
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  • 2009 H.A. Wheeler Applications Prize Paper Award

    Publication Year: 2009 , Page(s): 3711 - 3713
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  • 2009 S.A. Schelkunoff Transactions Prize Paper Award

    Publication Year: 2009 , Page(s): 3714 - 3715
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  • 2009 LAWP Piergiorgio L.E. Uslenghi Prize Paper Award

    Publication Year: 2009 , Page(s): 3716 - 3718
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  • 2009 IEEE Fellow Awards From the Antennas and Propagation Society

    Publication Year: 2009 , Page(s): 3719
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  • Optimal Characteristics of an Arbitrary Receive Antenna

    Publication Year: 2009 , Page(s): 3720 - 3727
    Cited by:  Papers (13)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (349 KB) |  | HTML iconHTML  

    Several fundamental questions about the operation of receiving antennas are addressed, such as ldquoWhy does a receiving antenna scatter an incident field?rdquo and ldquoUnder what conditions does a receive antenna capture all of the available incident power?rdquo A new method is described by which the received power can be maximized for an arbitrary receiving antenna. The technique is first illustrated for two-dimensional infinite receiving arrays of electric and/or magnetic dipole elements, which result in simple plane waves for the scattered (re-radiated) fields. Optimal results (for maximum received power) are derived for several cases, and it is established that half the available incident power may be received by an array of electric (or magnetic) elements in free space, and that all available incident power may be received by an array that combines electric and magnetic elements, or one that incorporates a ground plane. Next, an arbitrary finite three-dimensional antenna enclosed by a mathematical spherical surface is treated using spherical vector wave functions. It is shown that half the available incident power can be received by such an antenna consisting of either TM or TE only elements, while all available incident power can be received when both TM and TE elements are used. It is also shown that the absorption efficiency for any optimal arbitrary antenna is 50%. View full abstract»

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  • Miniaturization of the Biconical Antenna for Ultrawideband Applications

    Publication Year: 2009 , Page(s): 3728 - 3735
    Cited by:  Papers (16)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1171 KB) |  | HTML iconHTML  

    A miniaturized, ultrawideband antenna for the 3.1 to 10.6 GHz frequency band is presented. The antenna is designed to have a low profile to enhance integration onto existing structures and a low directivity pattern for body worn applications. A systematic process to miniaturize the well-known biconical antenna is illustrated by adding several different geometric features that reduce the size of the antenna. After miniaturization, the vertical height of the antenna was reduced by over 60% while maintaining electrical performance. Prototype antennas were manufactured using low cost plastic injection molding and dipping processes to facilitate transition to mass production and to enhance the durability of the antenna. The simulated and measured reflection coefficient of the antenna show good agreement. Measured antenna gain patterns verify that the manufacturing process employed is capable of producing low loss antenna structures. Lastly, time domain short pulse measurements of the antenna verify that it does not appreciably distort radiated signals in the azimuthal plane. View full abstract»

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  • UWB Self-Compensating Antennas: Numerical Demonstration of the Electromagnetic Working Principle

    Publication Year: 2009 , Page(s): 3736 - 3745
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1639 KB) |  | HTML iconHTML  

    To achieve a dispersionless channel, the receiver must counteract the dispersion caused by the transmitter, assuming that the propagating medium is dispersionless. If identical antennas are used for transmission and reception, constraints are placed on the antenna of interest, since the temporal transmit and receive responses of an antenna are linked through reciprocity and related by a time derivative. By invoking the concept of a half-derivative, it was proposed in Tyo's 2008 paper, that a half-differentiator transmitter in the time domain (TD) will operate as a half-integrator receiver over some range of frequencies. In the frequency domain (FD) this corresponds to a transfer function that behaves in a similar fashion as the 2D Green's function due to a line source. The required antenna should transmit and receive cylindrical waves efficiently. When used in UWB applications, a receiving antenna with this property will counteract its dispersion effect as a transmitter, providing a flat overall channel gain. In this work, a numerical model for a rotationally symmetric structure with a dielectric lens is used as a transmitter to verify the above proposition. We start by a brief explanation of the principle on which the antenna works as cylindrical source. A study of FD and TD parameters of the model are provided. The limitations due to the dielectric lens are also addressed, and other geometries of similar characteristics are modeled. In these examples, we demonstrate how the information contained in the radiated fields can help in predicting the flatness of channel gain. View full abstract»

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  • A Miniature Quadrifilar Helix Antenna for Global Positioning Satellite Reception

    Publication Year: 2009 , Page(s): 3746 - 3751
    Cited by:  Papers (14)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1303 KB) |  | HTML iconHTML  

    The design is described of a very compact quadrifilar helix antenna. A hollow ceramic rod is used as a dielectric load to reduce antenna size, which is only 2.7% of an air-loaded quadrifilar helix antenna. A simple equivalent circuit is established for the proposed quadrifilar helix antenna to demonstrate impedance characteristics. A self-phasing method for achieving circular polarization is also proposed. This method is convenient for tuning circular polarization. Additionally, a compact matching structure is designed to match the proposed antenna, which only utilizes short transmission-line sections and one capacitor. For experiments, the proposed antenna is designed at 1.575 GHz such that it can be utilized for global position system. Measurement and simulation results agree. A hemispherical pattern with a beamwidth of 150deg is measured. This circular-polarized pattern with a wide beamwidth is feasible for mobile applications. View full abstract»

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  • Dual Band Planar Spiral Feed Backed by a Stepped Ground Plane Cavity for Satellite Boresight Reference Antenna Applications

    Publication Year: 2009 , Page(s): 3752 - 3756
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (640 KB) |  | HTML iconHTML  

    This paper presents development of a new planar spiral feed for a satellite boresight reference antenna, operating at two widely separated frequency bands (2200-2300 MHz and 8000-8400 MHz). A stepped ground plane cavity with different quarter wavelength distances is proposed to provide unidirectional patterns at these frequency bands. A back lobe suppression of around 12 dB in 2 GHz band and better than 15 dB in 8 GHz band with a measured on-axis axial ratio of less than 3 dB is achieved for the dual band planar spiral feed with stepped ground plane cavity configuration. A boresight reflector antenna employing this feed has measured beamwidths of 7 degrees and 1.8 degrees respectively and gain of 26 dBi and 36 dBi at 2250 MHz and 8200 MHz. View full abstract»

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  • Dual-Band Circularly Polarized Dual-Slot Antenna With a Dielectric Cover

    Publication Year: 2009 , Page(s): 3757 - 3764
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (480 KB) |  | HTML iconHTML  

    A new circularly-polarized (CP) dual-slot antenna fed by a single L-probe is proposed for dual-band applications. The antenna consists of a zonal slot and an annular slot, both of them being cut onto a square conducting cavity with a protective dielectric cover. It is observed that the resonance frequencies of the lower and upper bands are controlled by the zonal and annular slots, respectively, making designs of the dual-band antenna very easy. To demonstrate the idea, the proposed antenna was designed at 2.4/5.8 GHz for two IMS bands. The reflection coefficient, axial ratio, radiation pattern and gain of the dual-band antenna were studied, and reasonable agreement between the simulated and measured results was obtained. A parametric study was carried out to characterize the proposed antenna. View full abstract»

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  • Foldable and Stretchable Liquid Metal Planar Inverted Cone Antenna

    Publication Year: 2009 , Page(s): 3765 - 3771
    Cited by:  Papers (22)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1196 KB) |  | HTML iconHTML  

    A mechanically flexible planar inverted cone antenna (PICA) for ultrawideband (UWB) applications is presented. It can be both folded and stretched significantly without permanent damage or loss of electrical functionality. The antenna is manufactured with a process in which conductors are realized by injecting room temperature liquid metal alloy into micro-structured channels in an elastic dielectric material. The elastic dielectric material together with the liquid metal enables bending with a very small radius, twisting, and stretching along any direction. Port impedance and radiation characteristics of the non-stretched and stretched antenna are studied in simulations and experiments. The presented antenna has a return loss better than 10 dB within 3-11 GHz and a radiation efficiency of > 70% over 3-10 GHz, also when stretched. Tests verify that stretching up to 40% is possible with maintained electrical performance. The presented antenna is useful for example for body-worn antennas and in applications in harsh environments where mechanical flexibility helps improve durability. View full abstract»

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  • An Eigencurrent Approach for the Analysis of Finite Antenna Arrays

    Publication Year: 2009 , Page(s): 3772 - 3782
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (634 KB) |  | HTML iconHTML  

    An accurate description of typical finite-array behavior such as edge effects and array resonances is essential in the design of various types of antennas. The analysis approach proposed in this paper is essentially based on the concept of eigencurrents and is capable of describing finite-array behavior. In the approach numerical simulation is carried out, first, by computing element eigencurrents from chosen expansion functions and, second, by expanding a limited set of array eigencurrents in terms of element eigencurrents that contribute to the mutual coupling in the array. Both types of eigencurrents are eigenfunctions of an impedance operator that relates the current to the excitation field. Highlighting both mathematical and physical features we describe the basic concepts of the approach, in particular the relation between eigenvalues and mutual coupling. We illustrate these features for uniform linear arrays of loops and dipoles, and demonstrate that the approach provides significant improvements in terms of computation time and memory use. View full abstract»

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  • Phase-Mode Processing for Spherical Antenna Arrays With a Finite Number of Antenna Elements and Including Mutual Coupling

    Publication Year: 2009 , Page(s): 3783 - 3790
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (313 KB) |  | HTML iconHTML  

    Spherical arrays are the answer to obtain an antenna array with isotropic properties. They are capable of receiving an electromagnetic wave with equal strength irrespective of the direction-of-arrival and the polarization. Yet, the construction of an antenna array with spherical symmetry is far from straightforward. In this paper we derive a compact description for the electromagnetic characteristics of a spherical array. Special care is taken to ensure the spherical symmetry of the array when the number of antenna elements is limited and when mutual coupling is present. Besides extra requirements for the individual antenna elements, an appropriate distribution of the antenna elements is required. By means of synthetic antenna data obtained with full-wave simulations we demonstrate that a spherical array provides efficient beam steering relying on the phase-mode excitation principle. View full abstract»

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  • Preliminary Investigations of a Low-Cost Ultrawideband Array Concept

    Publication Year: 2009 , Page(s): 3791 - 3799
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1711 KB) |  | HTML iconHTML  

    A design concept is presented that achieves ultra wideband (UWB) array performance with significantly fewer elements than the traditional approach of using a single wideband antenna element type to fully populate the array. Starting from a conventional 8:1 bandwidth array design of a given aperture size, an array of equivalent aperture and bandwidth is created using scaled elements of three different sizes. This wavelength-scaled equivalent array has fewer than 18% of the original element count, i.e., roughly 6-times fewer elements, a similar reduction in weight, and most importantly, a significant reduction in electronics required to feed the array. If proven viable, array architectures of this type could make UWB arrays significantly more cost effective. In this preliminary numerical study, rigorous full-wave simulation tools are used to test the performance of small but informative wavelength-scaled array configurations of flared-notch radiators for the single-polarization case. View full abstract»

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  • Linear Array Thinning Exploiting Almost Difference Sets

    Publication Year: 2009 , Page(s): 3800 - 3812
    Cited by:  Papers (45)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1581 KB) |  | HTML iconHTML  

    This paper describes a class of linear thinned arrays with predictable and well-behaved sidelobes. The element placement is based on almost difference sets and the array power pattern is forced to pass through N uniformly-spaced values that, although neither equal nor constant as for difference sets, are a-priori known from the knowledge of the aperture size, the number of active array elements K, and the features of the correlation function. Such a property allows one to predict the bounds of the confidence range of the peak sidelobe of the admissible arrays obtainable through simple shift operations on a binary sequence. The expected peak sidelobe performances turn out to be comparable with those from difference sets, even though obtainable in a wider set of array configurations, and improved in comparison with cut-and-try random-placements. View full abstract»

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  • Focused Microstrip Array Antenna Using a Dolph-Chebyshev Near-Field Design

    Publication Year: 2009 , Page(s): 3813 - 3820
    Cited by:  Papers (22)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1764 KB) |  | HTML iconHTML  

    A new concept in designing large array antennas to focus the microwave power in the radiation near-field region is presented. A small focused array antenna using microstrip patch elements to achieve the desired sidelobes levels in the Fresnel region based on Dolph-Chebyshev design is implemented. This array is built to verify the concept, and then the measured and computed near fields are compared to verify the accuracy of the design. Larger arrays are designed by using the knowledge of the mutual admittances between the elements of smaller arrays. Several computed examples are presented in order to show some properties of focusing arrays. It is shown that the maximum intensity of the electric field along the axial direction is displaced from the focal point towards the antenna aperture. This displacement decreases as the aperture size increases. View full abstract»

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  • Amplitude and Phase Controlled Reflectarray Element Based on an Impedance Transformation Unit

    Publication Year: 2009 , Page(s): 3821 - 3826
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2125 KB) |  | HTML iconHTML  

    An architecture to simultaneously affect both amplitude and phase control from a reflectarray element using an impedance transformation unit is demonstrated. It is shown that a wide range of control is possible from a single element, removing the conventional necessity for variable sized elements across an array in order to form a desired reflectarray far-field pattern. Parallel plate waveguide measurements for a 2.2 GHz prototype element validate the phase and amplitude variation available from the element. It is demonstrated that there is sufficient control of the element's reflection response to allow Dolph-Tschebyscheff weighting coefficients for major-lobe to side-lobe ratios of up to 36 dB to be implemented. View full abstract»

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  • Electromagnetic Radiation by Antennas of Arbitrary Shape in a Layered Spherical Media

    Publication Year: 2009 , Page(s): 3827 - 3834
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (600 KB) |  | HTML iconHTML  

    A unified method of moments model is developed for the analysis of arbitrarily shaped antennas that are radiating next to a multilayered dielectric sphere. The curvilinear Rao-Wilton-Glisson triangular basis functions and dyadic Green's functions have been used in the model. Antennas of various geometries including spherical, circular and rectangular microstrip antennas as well as hemispherical dielectric resonators have been modeled. Input impedance and radiation pattern results are presented and shown to be in good agreement with published data. 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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Meet Our Editors

Editor-in-Chief                                                 Kwok W. Leung