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# IEEE Transactions on Antennas and Propagation

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Displaying Results 1 - 25 of 42

Publication Year: 2009, Page(s):C1 - 1589
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• ### IEEE Transactions on Antennas and Propagation publication information

Publication Year: 2009, Page(s): C2
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• ### Modified $theta$-Scanning Technique for First/Third-Order Probes for Spherical Near-Field Antenna Measurements

Publication Year: 2009, Page(s):1590 - 1596
Cited by:  Papers (3)
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This paper presents a modified thetas-scanning technique for first/third-order probes for spherical near-field antenna measurements. Unlike the traditional thetas-scanning technique, this new scanning technique gives a possibility, due to the cutoff property of the azimuthal spherical modes, to filter out the influence of the undesired third-order azimuthal modes of the probe near the poles of the... View full abstract»

• ### An Ultrawideband Diversity Antenna

Publication Year: 2009, Page(s):1597 - 1605
Cited by:  Papers (77)
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A compact diversity antenna operating at an ultrawideband (UWB) frequency range of 3.1-5 GHz is proposed for use in portable devices. The antenna printed on a printed circuit board (PCB) slab consists of two notched triangular radiating elements with two feeding ports. A ground plane is etched on the reverse side of the PCB. The shape of the ground plane is optimized to improve the isolation betwe... View full abstract»

• ### Time-Domain Circularly Polarized Antennas

Publication Year: 2009, Page(s):1606 - 1611
Cited by:  Papers (7)
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The transient properties of short-pulsed elliptically/ circularly polarized antennas, namely, the transmitting and receiving effective heights, are introduced. Due to the pulsed temporal dependence of the radiation pattern, an instantaneous axial ratio is introduced as a quality measure of the polarization performance. For these antennas, it is shown that the trace of the tip of the electric-field... View full abstract»

• ### Microstrip Patch Antennas on Tunable Electromagnetic Band-Gap Substrates

Publication Year: 2009, Page(s):1612 - 1617
Cited by:  Papers (32)  |  Patents (3)
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A tunable metamaterial in integrated circuit structures is investigated through an example of a microstrip patch antenna on a mushroom-type electromagnetic band-gap (EBG) structure. The patch antenna is designed as a half-wavelength resonator of an EBG loaded microstrip transmission line. The operating frequency of a patch antenna can be switched and controlled dynamically by loading diode switche... View full abstract»

• ### Miniature Antenna Using Printed Coupled Lines Emulating Degenerate Band Edge Crystals

Publication Year: 2009, Page(s):1618 - 1624
Cited by:  Papers (29)
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A miniature printed antenna design that exploits higher-order dispersion behavior in degenerate band edge (DBE) crystals is proposed. First, the unit cell of a DBE crystal is emulated using a simple combination of uncoupled and coupled microstrip (MS) line sections printed on a low loss dielectric substrate. Subsequently, a resonant antenna is formed by cascading two such MS-DBE unit cells in a ci... View full abstract»

• ### Unbalanced-Mode Spiral Antenna Backed by an Extremely Shallow Cavity

Publication Year: 2009, Page(s):1625 - 1633
Cited by:  Papers (32)
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This paper describes a two-arm Archimedean spiral antenna backed by a conducting cavity, where only one arm is directly excited, with the other arm being parasitically excited; in other words, the spiral arms are excited in an unbalanced mode. A balun circuit required for a conventional two-arm spiral is not used for this unbalanced-mode spiral. The design of the unbalanced-mode spiral is performe... View full abstract»

• ### Minimizing the Noise Penalty Due to Mutual Coupling for a Receiving Array

Publication Year: 2009, Page(s):1634 - 1644
Cited by:  Papers (47)
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For phased array receivers, mutual coupling leads to beam-dependent active impedances which must be taken into account when matching the array ports to front end amplifiers for optimal noise performance. We study the noise penalty for several noise matching conditions and develop a matching condition that minimizes the average beam equivalent receiver noise temperature over multiple beams. For non... View full abstract»

• ### Fast Beamforming for Mobile Satellite Receiver Phased Arrays: Theory and Experiment

Publication Year: 2009, Page(s):1645 - 1654
Cited by:  Papers (22)
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The purpose of this paper is to present a robust and fast beamforming algorithm for the low-cost mobile phased array antennas. The proposed beamforming algorithm uses a sequentially perturbation gradient estimation method to update the control voltages of the phase shifters, with the objective of maximizing the received power by the array. This algorithm does not require either the knowledge of ph... View full abstract»

• ### Beamforming in the Presence of Mutual Coupling Based on Constrained Particle Swarm Optimization

Publication Year: 2009, Page(s):1655 - 1666
Cited by:  Papers (20)
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Two approaches towards beamforming based on constrained particle swarm optimization (PSO) are presented. One approach relies on the penalty function method, for which a new mathematical expression to select the penalty factors is derived. The other method uses a new PSO strategy for solving constrained optimization problems. To maximize performance of the beamforming procedure, the optimal system ... View full abstract»

• ### Conceptual Study of Analog Baseband Beam Forming: Design and Measurement of an Eight-by-Eight Phased Array

Publication Year: 2009, Page(s):1667 - 1672
Cited by:  Papers (8)  |  Patents (5)
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We report on the design and measurement of an eight-by-eight modular phased array that uses analog quadrature baseband phase shifters. The array is designed for 2.4 GHz and has a few MHz of bandwidth. Though for such frequency, bandwidth and number of elements, digital beam forming is still feasible with contemporary analog-to-digital converters (ADC), the design is a proof of concept for analog b... View full abstract»

• ### Printed S-Band 4 $times$ 4 Nolen Matrix for Multiple Beam Antenna Applications

Publication Year: 2009, Page(s):1673 - 1678
Cited by:  Papers (23)
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A Nolen matrix design method is proposed as an asymptotic singular case of a recent Blass matrix design algorithm. The procedure is illustrated by a 4 x 4 Nolen matrix, which design is centred at 2.2 GHz, with the amplitude and phase output excitation laws of a Butler matrix using 90deg hybrids. Simulation and measurement results are presented in this paper. View full abstract»

• ### Rapid Method for Finding Faulty Elements in Antenna Arrays Using Far Field Pattern Samples

Publication Year: 2009, Page(s):1679 - 1683
Cited by:  Papers (15)
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A simple and fast technique that allows a diagnosis of faulty elements in antenna arrays, that only needs to consider a small number of samples of its degraded far-field pattern is described. The method tabulates patterns radiated by the array with 1 faulty element only. Then, the pattern corresponding to the configuration of failed/unfailed elements under test is calculated using the error-free p... View full abstract»

• ### Design of Subarrayed Linear and Planar Array Antennas With SLL Control Based on an Excitation Matching Approach

Publication Year: 2009, Page(s):1684 - 1691
Cited by:  Papers (26)
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In this paper, the synthesis of subarrayed antennas with subarrays having different weights and dimensions is considered. The problem is formulated as the definition of the element clustering into spatially contiguous subarrays and the corresponding weights to obtain a pattern with the lowest (i.e., minimum achievable) sidelobe level (SLL). The problem is addressed with an unconstrained approach b... View full abstract»

• ### Radar-Based Breast Cancer Detection Using a Hemispherical Antenna Array—Experimental Results

Publication Year: 2009, Page(s):1692 - 1704
Cited by:  Papers (180)  |  Patents (2)
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In this contribution, an ultrawideband (UWB) microwave system for breast cancer detection is presented. The system is based on a novel hemispherical real-aperture antenna array, which is employed in a multi-static radar-based detection system. The array consists of 16 UWB aperture-coupled stacked-patch antennas located on a section of a hemisphere. The radar system is designed to be used with real... View full abstract»

• ### Experimental Tests of Microwave Breast Cancer Detection on Phantoms

Publication Year: 2009, Page(s):1705 - 1712
Cited by:  Papers (30)
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We report on experimental tests of microwave breast cancer detection using the radar-based imaging method and breast phantoms, i.e., structures whose size and shape are similar to reality, and whose electric properties are close to those known for the normal and tumoral tissues. Different antennas have been designed, fabricated and tested in operation in the experimental setup. Measurements were c... View full abstract»

• ### 94-GHz Imager With Extended Depth of Field

Publication Year: 2009, Page(s):1713 - 1719
Cited by:  Papers (5)
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We describe a computational imaging technique to extend the depth-of-field of a 94-GHz imaging system. The technique uses a cubic phase element in the pupil plane of the system to render system operation relatively insensitive to object distance. However, the cubic phase element also introduces aberrations but, since these are fixed and known, we remove them using post-detection signal processing.... View full abstract»

• ### Free-Space Imaging Beyond the Diffraction Limit Using a Veselago-Pendry Transmission-Line Metamaterial Superlens

Publication Year: 2009, Page(s):1720 - 1727
Cited by:  Papers (32)
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Focusing using conventional lenses relies on the collection and interference of propagating waves, but discounts the evanescent waves that decay rapidly from the source. Since these evanescent waves contain the finest spatial details of the source, the image suffers a loss of resolution and is referred to as ldquodiffraction-limited.rdquo Superlensing is the ability to create an image with fine fe... View full abstract»

• ### A High-Performance Upgrade of the Perfectly Matched Layer Multilevel Fast Multipole Algorithm for Large Planar Microwave Structures

Publication Year: 2009, Page(s):1728 - 1739
Cited by:  Papers (15)
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An improvement of the perfectly matched layer multilevel fast multipole algorithm (PML-MLFMA) for simulating large planar microwave structures is presented. By exploiting the low-rank property of the PML-MLFMA multimodal aggregation and disaggregation matrices, considerable reductions in memory usage and computation time are obtained. The method has been extensively validated, demonstrating comple... View full abstract»

• ### A Hierarchical Partitioning Strategy for an Efficient Parallelization of the Multilevel Fast Multipole Algorithm

Publication Year: 2009, Page(s):1740 - 1750
Cited by:  Papers (67)
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We present a novel hierarchical partitioning strategy for the efficient parallelization of the multilevel fast multipole algorithm (MLFMA) on distributed-memory architectures to solve large-scale problems in electromagnetics. Unlike previous parallelization techniques, the tree structure of MLFMA is distributed among processors by partitioning both clusters and samples of fields at each level. Due... View full abstract»

• ### Iterative Solutions of Hybrid Integral Equations for Coexisting Open and Closed Surfaces

Publication Year: 2009, Page(s):1751 - 1758
Cited by:  Papers (10)
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We consider electromagnetics problems involving composite geometries with coexisting open and closed conductors. Hybrid integral equations are presented to improve the efficiency of the solutions, compared to the conventional electric-field integral equation. We investigate the convergence characteristics of iterative solutions of large composite problems with the multilevel fast multipole algorit... View full abstract»

• ### An ADI-PE Approach for Modeling Radio Transmission Loss in Tunnels

Publication Year: 2009, Page(s):1759 - 1770
Cited by:  Papers (27)
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Alternate direction implicit (ADI) method is used to study radio wave propagation in tunnels using the parabolic equation (PE). We formulate the ADI technique for use in tunnels with rectangular, circular and arched cross sections and with lossy walls. The electrical parameters of the lossy walls are characterized by an equivalent surface impedance. A vector PE is also formulated for use in tunnel... View full abstract»

• ### On the Space-Time Variations of Rain Attenuation

Publication Year: 2009, Page(s):1771 - 1782
Cited by:  Papers (19)
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Rain attenuation shows a considerable temporal and spatial variability. To simulate fade mitigation techniques such as route diversity, a space-time channel model which accounts for the spatial and temporal variation of rain attenuation is needed. In this paper we investigate the space-time correlation of rain attenuation utilizing 42 GHz star-like network measurements. By combining the spatial an... View full abstract»

• ### Free Space Optical System Performance for a Gaussian Beam Propagating Through Non-Kolmogorov Weak Turbulence

Publication Year: 2009, Page(s):1783 - 1788
Cited by:  Papers (42)
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Atmospheric turbulence has been described for many years by Kolmogorov's power spectral density model because of its simplicity. Unfortunately several experiments have been reported recently that show Kolmogorov theory is sometimes incomplete to describe atmospheric statistics properly, in particular in portions of the troposphere and stratosphere. It is known that free space laser system performa... View full abstract»

## Aims & Scope

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

Full Aims & Scope

## Meet Our Editors

Editor-in-Chief                                             Danilo Erricolo