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Radar cross section (RCS) images describe position and scattering brightness of scattering centers of a radar target, but lack information about the underlying scattering mechanisms. This information can be valuable help for the design of radar targets, as soon as it becomes available. The proposed method uses a polarimetric approach to detect and discriminate three different scattering mechanisms, independently of the orientation of the scatterers. These mechanisms can be separately visualized for easy interpretation of the physical processes occurring at the radar target. Measurement results recorded in a compact range demonstrated the practical applicability of this approach. [ABSTRACT FROM AUTHOR]

This paper provides the experimental assessment of an effective near-field-to-far-field (NF-FF) transformation technique with spherical-spiral scanning, particularly suitable for long antennas. Such a technique allows a remarkable measurement-time saving, due to the use of continuous and synchronized movements of the positioning systems, and due to the reduced number of required near-field measurements. This is made possible by a non-redundant sampling representation of the voltage measured by the probe, obtained by using the unified theory of spiral scans for non-spherical antennas, and adopting a prolate-ellipsoidal source modeling. The near-field data needed by the classical spherical near-field-to-far-field transformation are then efficiently retrieved from those acquired along the spiral by an optimal sampling interpolation formula. [ABSTRACT FROM AUTHOR]

Traditional wireless position-location systems, operating using propagating waves, suffer reduced performance in non-line-of-sight (NLoS) applications. Traditional systems that use quasistatic fields have instead been limited to short ranges, progressive direction-finding applications, require RF fingerprinting, or do not provide complete immunity to dielectric obstacles (use of electric fields). These limitations impose severe restrictions in applications such as tracking an American football during game play, where position and orientation tracking may be required over long ranges, and when the line-of-sight (LoS) is blocked by groups of people. A technique using magneto-quasistatic fields and complex image theory was recently shown to circumvent these problems, and to enable accurate long-range one-dimensional and two-dimensional measurements. In this work, we present three-dimensional position and orientation measurements using the magneto-quasistatic system and complex image theory over an area of 27.43 m ? 27.43 m. Inverting the theoretical expression for the voltage measured at the terminals of the receiving loops to determine three-dimensional position and orientation resulted in mean and median geometric position errors of 0.77 m and 0.71 m, respectively; inclination orientation mean and median errors of 9.67? and 8.24?, respectively; and azimuthal orientation mean and median errors of 2.84? and 2.25?, respectively. [ABSTRACT FROM PUBLISHER]

This article describes the possible factors that can introduce discrepancies between measurements and three-dimensional EM simulations of millimeter-wave (mm-wave) antennas. The effects of the choice of the simulation solver, the relative permittivity and the homogeneity of the substrate material, the manufacturing tolerance, and the measurement errors are discussed. It is concluded that a fair comparison between measurements and simulations of mm-wave antennas can only be made if all these possible causes of discrepancies are taken into account. [ABSTRACT FROM AUTHOR]

Based on the vector resolution of the orthogonal components of a circularly polarized signal, and the known perpendicular and parallel transmission coefficients of a dielectric radome panel or EM Window, a method is presented using a standard computer spreadsheet to predict both the circularly polarized attenuation (CPA) and the cross-polarization-ratio (XPR) performance of the panel. [ABSTRACT FROM AUTHOR]

The article narrates the authors inclination to serve as associate editors for the measurements corner of the journal. Brian Fischer states that he brings passion for measurements and that he is privileged to serve as co-associate editor for the measurements corner. Ivan LaHaie also expresses his excitement to serve as co-associated editor. He shares with Fischer goal for the measurement corner to see theory, predictions and measurement converge for a variety of radar and antenna problems.

Summary form only. Abstract of the paper, "Smart characterization of an AESA radar front-end by non-redundant near-field measurements." [ABSTRACT FROM AUTHOR]

The article focuses on the measurement of the differential impedance of a balanced device by comparing three methods. Topics discussed include the s-parameter, the balun, and the mixed-mode S-parameter. It mentions that these methods were used to measure the known differential impedance of a broadband balanced load, and the unknown differential impedance of a narrowband balanced micro strip patch antenna.

A key concern in making near-fi eld antenna measure ments is measurement time, since most often the use of near-fi eld processes entails stepping up to additional sampling. This month's Measurements Corner article features excellent antenna-measurement comparisons based on derived non-redundant minimum near-fi eld samples for two fundamentally different collection geometries. [ABSTRACT FROM AUTHOR]

This month's Measurements Corner article, by Ron Pogorzelski (Pogo, to many if us), features a very interesting application of a constrained iterative algorithm for solving a linear system of equations to the problem of antenna diagnostics. The paper presents both an intuitive description and a mathematical derivation of the technique, along with a numerical example of its capability. [ABSTRACT FROM PUBLISHER]

The return-loss measurement is a measurement that all antenna engineers are well familiar with, but such great familiarity can (and often does) lead to cavalier use. Lever aging a 2009 Magazine contribution, this month's Measurements Corner briefly revisits the original definition of return loss compared to some current common usage. [ABSTRACT FROM AUTHOR]

Most of we engineers would say that we have fun doing our jobs, but there probably are not too many of us who can back it up like the authors of this month's Measurements Corner article. After all, combining football (or as they put it, “American football”) with fields and waves has to be about as good as it gets. The article describes a concept in the very rapidly growing area of sports visualization technology, namely the tracking of a football using magneto-quasistatic signals. [ABSTRACT FROM AUTHOR]

The article offers information about "quasi-raster," a method developed by Integrity Applications Inc. for improving the accuracy of data along the edges by controlling the truncation error in near-field antenna. The proposed method is used for aperture antennas and planar scanning which allows selection of measurement sampling points.

The article offers information on the measurement of tunnels or drainage system for analyzing the behavior of the radio signals inside it. It informs that this is a major concerning area for the several Asian countries because the drainage systems in these countries are different from those in the European countries. It further states that studying the wave propagation inside the tunnels, serves as a useful indicator for designing the reliable wireless communication systems for drains.

Antenna-measurement practitioners who have the luxury of a perfect measurement facility will fi nd little of interest in this issue's Measurements Corner contribution. For the rest of us, the paper by Álvarez, et al. offers a collections of methods based on maximum-likelihood estimation for characterizing and correcting errors due to stray multipath in antenna-meas urement facilities. Both detailed derivations and experimental examples are presented. [ABSTRACT FROM PUBLISHER]

The article introduces the paper "Small Device for Short-Range Antenna Measurements Using Optics," by Boyan Yanakiev et al. in the December 2011 issue of the "IEEE Antennas and Propagation Magazine."

The article provides information on the "Measurements Corner" paper of the "IEEE Antennas & Propagation Magazine" for the October 2011 issue.

The problem of detecting, locating, and tracking dismounts (moving people), using a distributed collection of simple and cheap narrowband (and, hence, low-resolution) radar devices, is an extremely challenging problem. It has been a topic of considerable research for the past several years. In particular, system performance is dependent upon both the positioning of the devices and the detection/tracking algorithms applied to the raw radar data. This month's Measurements Comer paper describes a novel Bayes-optimal nonlinear filtering technique for the latter. It demonstrates that reasonable dismount tracking can be accomplished with 5–10m bistatic range-resolution systems. [ABSTRACT FROM PUBLISHER]

We welcome contributions for future installments of the Measurements Comer. Please send them to Brian Fischer and Ivan LaHaie, and they will be considered for publication as quickly as possible. Contributions can range from short notes to fun-length papers on all topics related to RF measurement technology and its applications, including antennas, propagation, materials, scattering, and radar cross section. New or unique measurement techniques are of particular interest. [ABSTRACT FROM PUBLISHER]

The article calls for contributions for future installments of the Measurements Corner of the "IEEE Antennas & Propagation Magazine," and advises to sent all articles to Brian Fischer and Ivan J. LaHaie, both of Integrity Applications Inc.

An introduction to an article about a domain-filtering method of isolating the radiation pattern of an individual radiator in measured data from other radiators that constitute a complex radiation distribution is presented.

The article lists the technical experts behind the Measurements Corner column for the August 2008 issue of "IEEE Antennas and Propagation Magazine" which includes Brian E. Fischer and Ivan J. LaHaie.