Horizontal Wire Antenna Research Articles

Typical Constructs in Unveiling the Horizontal Wire Antenna

Typical Constructs in Unveiling the Horizontal Wire Antenna

Exact EM field excited by a short horizontal wire antenna lying on a conducting soil

To date, only under restrictive assumptions can we derive closed-form expressions for the fields generated by an electrically small horizontal wire antenna situated on a planar conducting soil. Such assumptions limit the validity of the derived formulas to specified frequency ranges, or to the case of highly-conducting material media. The purpose of this work is to relax all the constraints underlying the derivation of the previously published solutions to this half-space problem, and develop an analytical technique that allows to reduce the integral representations for the field components generated by the dipole source to a well-known elementary contour integral, whose evaluation is straightforward. Numerical results are presented to show the advantages of the obtained explicit formulas, which are valid regardless of the operating frequency, over the previous solutions.

Investigation of Using High Impedance Surfaces for Wide-Angle Scanning Arrays

In this paper, an eight-element linear array is proposed and experimentally studied to illustrate the potential of using high impedance surfaces (HISs) for wide-angle scanning applications. An HIS-based horizontal wire antenna with a broad-beam radiation pattern is implemented as the individual radiating elements of the proposed array. The working mechanism of the HIS-based array is investigated as well. The rectangular-mushroom HIS, operating in surface-wave band, contributes to the broad-beam radiation of the individual antenna element as well as the wide scan performance of the array. Measured results show that with uniform magnitude and progressive phase excitation, the array performs a wide scan angle up to 85° in the elevation plane and a realized gain varying from 13.1 to 10.1 dBi. Meanwhile, the side lobe levels (SLLs) are generally less than $-10\;\mathbf{dB}$ over the entire scan region. Good agreement is obtained between the measurements and the simulations.

Comparison of atmospheric electric field measurements by a pole mounted fieldmeter and by a horizontal wire antenna

The studies reported show that measurements of atmospheric electric fields by pole mounted electrostatic fieldmeters can match measurements by a horizontal antenna wire. Some differences were experienced early in the tests that cannot yet be explained. The differences are tentatively attributed to tribocharging actions during initial set up of the antenna system and by wind blown airborne particulates at the antenna wire. Pole mounted fieldmeters provide opportunity for long term unattended measurements in quite adverse weather conditions with continuous checking of operational health against debris, spider's webs, etc.

Measurement of atmospheric air-earth current density from a tropical station using improvised Wilson’s plate antenna

Abstract We have developed an experimental set-up to measure the atmospheric air-earth current (conduction current). Data obtained with the continuous measurements of Wilson’s plate are used to study of air-earth current density, with the aim of gaining an understanding of the experimental set-up’s response to different meteorological conditions, including fair-weather days. This paper is a part of the on-going Global Electric Circuit (GEC) studies from Tirunelveli (8.7°N, 77.8°E), a measurement site in the tropical and southern tip of the Indian peninsula. Attempts have been made in past few years to obtain the global signature in this region with this sensor, but on most of the occasions it has been impossible to obtain the global signature during fair-weather days. The data used for February–April, 2007 have the well-defined nature of this global signature, which is in agreement with the well-established classical Carnegie curve of GEC. This paper also deals with very important observations made at sunrise and during those hours when fog existed. It is noted that the resistivity of the atmosphere increased significantly with the onset of fog and later decreased as the fog disappeared, based on the measured value of conduction current density when compared with the electric field measured by horizontal passive wire antenna. Also, during fair-weather conditions, conduction current and electric field variations are similar because the conductivity during this period is more or less constant at this site. Observations made during different meteorological conditions, such as different wind speeds, humidities, and temperatures, are also discussed.

AN ANALYTIC FORMULA OF THE CURRENT DISTRIBUTION FOR THE VLF HORIZONTAL WIRE ANTENNA ABOVE LOSSY HALF-SPACE

An analytical formula of the current distribution for the VLF horizontal wire antenna located above the ground is presented in this paper. This formula is suitable for the VLF horizontal antenna which is fed at arbitrary position and with arbitrary loaded impedance at the end. In order to validate the analytical formula, a numerical code based on MoM is also developed. The comparison between the results obtained by two methods proves the validity of the analytical formula proposed in this paper.

COMPARATIVE STUDY ON VARIOUS ARTFICIAL MAGNETIC CONDUCTORS FOR LOW-PROFILE ANTENNA

Abstract—This paper investigated comparatively the characteristics of four types of artificial magnetic conductor (AMC) surface, including a mushroom-like (electromagnetic band gap) EBG, uniplanar compact EBG (UC-EBG), Peano curve, and Hilbert curve, as a ground plane for a low-profile antenna. The AMC surface structures are designed to have an in-phase reflection property for a plane wave of normal incidence in the vicinity of 2.45 GHz. The bandwidths of the in-phase reflection for the AMC surfaces and return losses, radiation patterns, and gains of the horizontal wire antennas on the AMC ground planes are all measured and compared with each other. The measured data show that all the AMC surfaces act as good ground planes for a lowprofile antenna, yet the bandwidth and gain of the mushroom-like EBG structure are broader and larger, respectively, than those of the other structures.

Artificial magnetic conductor using split ring resonators and its applications to antennas

AbstractAn artificial magnetic conductor using the split‐ring resonators (SRRs) printed on conductor‐backed dielectric substrate is presented. The simulation and measurement verify that the magnetic conductor is successfully accomplished around the resonant frequency. As an antenna application, the characteristics of a horizontal wire antenna placed above the SRR array, as well as a conducting ground plane and a grounded dielectric slab, are investigated and compared. A maximum gain of 4.34 dBi is obtained for the wire antenna above the SRR array. The results confirm that the split resonators can successfully be used to replace the antenna ground plane in order to improve their performance. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 329–334, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21341

A comparative study of atmospheric Maxwell current and electric field from a low latitude station, Tirunelveli

Simultaneous measurements of atmospheric Maxwell current and electric field, using horizontal long wire antenna and passive horizontal wire antenna system at 1 m above the Earth’s surface, were carried out at Tirunelveli (8.7°N, 77.8°E), India, during January/February 2002. The objectives of the present work have been to understand the nature of the measured atmospheric electrical parameters and explore the possibility of detecting the signature associated with the global thunderstorm activity. As the measurements indicate, the atmospheric electrical parameters at Tirunelveli are severely masked by the locally induced current components during disturbed weather conditions, for example, severe convective activity. During the selected fair weather conditions, the hourly averaged diurnal variation curves of Maxwell current and electric field are characterized by two peaks: The first peak is the local “sunrise effect” and the second peak occurs at times close to 1900 UT, the time of maximum global thunderstorm activity as noted in the famous “Carniege curve”. The correlation coefficient between the measured Maxwell current and electric field has a high value (more than 0.8) for all the fair weather days. These results support our view that this site is free from local pollution during the fair weather conditions and is suitable for long-term measurements of atmospheric electrical parameters.

An antenna electrometer system for atmospheric electrical measurements

A ±300 V dynamic range, battery-powered, and inexpensive electrometer system is described that has been used with passive horizontal wire antennas to measure the atmospheric electric potential at 1 and 2 m above the earth’s surface. Input currents drawn by the electrometer circuit are of order femtoamperes, and a guard drive output is provided to minimize leakage. The implementation of the passive wire antenna is described, using rigorous insulation and signal guarding, together with results obtained in fair weather conditions. Linearity of the portable electrometer over the input range is demonstrated to be comparable with a commercial laboratory electrometer, and the antenna potential can be determined to within a few volts in the fair weather electric field. Several such portable systems can be cheaply combined, sharing a common high tension supply, to measure the profile of the atmospheric electrical potential above the surface, at a remote site. Damage to the electrometer sustained in electrical storms can be cheaply repaired.

Impedance Calculations for Horizontal Wire Antennas Above a Lossy Earth

The input impedance of a thin cylindrical wire antenna kept horizontally above a lossy earth (modeled as a half-space) is calculated by solving the electric field integral equation for the antenna current using the method of moments (MoM). Coupled horizontal wire antennas kept at the same height from the air-earth interface are analyzed by solving the corresponding zero and first phase sequence current integral equations. Mutual impedance results for broadside and collinear configurations are presented. The earlier used MoM solution is used to calculate the input impedance of a horizontal wire antenna above a two-layered earth. This investigation is useful to determine the sensitivity of the antenna impedance to the changes arising from subsurface anomalies. The Sommerfeld-type integrals encountered in these analyses are evaluated by an accurate Gaussian integration method.

Introduction to special section: Atmospheric electricity: An IUGG symposium

Journal of Geophysical Research: AtmospheresVolume 101, Issue D23 p. 29607-29608 Free Access Introduction to special section: Atmospheric electricity: An IUGG symposium Robert H. Holzworth, Robert H. HolzworthSearch for more papers by this author Robert H. Holzworth, Robert H. HolzworthSearch for more papers by this author First published: 01 December 1996 https://doi.org/10.1029/96JD03163Citations: 1AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL No abstract is available for this article. References Adlerman, E. J., andE. R. Williams, Seasonal variation of the global electrical circuit,J. Geophys. Res., 101(D23), 1996. Avila, E. A., G. G. A. Varela, andG. M. Caranti, Charging in ice-ice collisions as a function of the ambient temperature and the larger-particle average temperature,J. Geophys. Res., 101(D23), 1996. Dowden, R. L., J. B. Brundell, W. A. Lyons, Are VLF rapid onset, rapid decay perturbations produced by scattering off sprite plasma?, J. Geophys. Res., 101, 19175– 19183, 1996. Eack, K. B., W. H. Beasley, W. D. Rust, T. C. Marshall, andM. Stolzenburg, Initial results from simultaneous observations of X rays and electric fields in a thunderstorm,J. Geophys. Res., 101(D23), 1996. Fernsler, R. F., andH. L. Rowland, Models of lightning-produced sprites and elves,J. Geophys. Res., 101(D23), 1996. Kirkland, M. W., B. A. Tinsley, andJ. T. Hoeksema, Are stratospheric aerosols the missing link between tropospheric vorticity and Earth transits of the heliospheric current sheet?,J. Geophys. Res., 101(D23), 1996. Lyons, W. A., Sprite observations above the U.S. high plains in relation to their parent thunderstorm systems,J. Geophys. Res., 101(D23), 1996. Murphy, M. J., E. P. Krider, andM. W. Maier, Lightning charge analyses in small CaPE storms,J. Geophys. Res., 101(D23), 1996. Pinto Jr., O., R. B. B. Gin, I. R. C. A. Pinto, O. Mendez Jr., J. H. Diniz, andA. M. Carvalho, Cloud-to-ground lightning flash characteristics in southeastern Brazil for the 1992–1993 summer season,J. Geophys. Res., 101(D23), 1996. Satori, G., andB. Zieger, Spectral characteristics of Schumann resonances observed in central Europe,J. Geophys. Res., 101(D23), 1996. Sentman, D. D., E. M. Wescott, Observations of upper atmospheric optical flashes recorded from an aircraft, Geophys. Res. Lett., 20, 2857– 2860, 1993. Tammet, H., S. Israelsson, E. Knudson, andT. J. Tuomi, Effective area of a horizontal long wire antenna collecting the atmospheric electric vertical current,J. Geophys. Res., 101(D23), 1996. Tinsley, B. A., Correlations of atmospheric dynamics with solar wind induced changes of air-Earth current density into cloud tops,J. Geophys. Res., 101(D23), 1996. Citing Literature Volume101, IssueD2327 December 1996Pages 29607-29608 This article also appears in:Atmospheric Electrodynamics ReferencesRelatedInformation

Note on: Fields of a horizontal wire antenna over a layered half-space

A previous analysis for a horizontal loop antenna is extended to deal with a horizontal wire antenna located over a layered half-space. As before, the exact solution so obtained is reduced to known special cases for the T.M.(transverse magnetic) and T.E. (transverse electric) radiated fields. These expressions are valid for zero or small heights above the air/ground interface. The application to a flat lying butterfly antenna, as a source, is also outlined.

ELF radio wave propagation in a locally nonuniform Earth‐ionosphere cavity

The vertical electric field component of the ELF radio wave propagating in the spherical Earth‐ionosphere cavity with a localized nonuniformity is studied. The analysis is performed in the framework of Born's approximation of the perturbation theory applied to the Stratton‐Chu integral equation. Both the vertical electric dipole and the horizontal grounded wire antenna are considered as the ELF field sources. It is shown that different effects can arise within the nonuniform waveguide depending on the disturbance position between or beyond the endpoint of the propagation path that are conditioned by the vectorial nature of the radio wave. Backscatter is the prevailing effect in the case of impedance or height disturbances. A localized nonuniformity can bring forth pattern rotation of the horizontal wire antenna and at the same time an amplitude modification of its lobes.

The circuit properties and complete fields of horizontal-wire antennas and arrays over earth or sea

The surface-wave and space-wave components of the electromagnetic field generated by a wave antenna of the Beverage or horizontal-wire type are determined and discussed. A knowledge of this complete field in the air over a conducting or dielectric half-space is essential for an over-the-horizon radar that makes use of both ionospheric reflection for detecting distant high-flying targets and the surface wave for detecting near and low-flying targets. Omnidirectional and directive arrays that include both wave antennas and a vertical monopole are described and analyzed.

A comparative numerical study of several techniques for modeling a horizontal wire antenna over a lossy half‐space

The electric‐field integral equation for the current on a thin, horizontal wire antenna radiating above a lossy half‐space is solved by the method of moments, with the effect of interface included via the Sommerfeld integrals, the well‐known reflection‐coefficient approximation and the high‐contrast approximation. A modified implementation of the reflection‐coefficient approximation is suggested, which makes this technique reasonably accurate for antennas near the interface. A comparison is made between the methods for several cases of practical interest. The high‐contrast approximation is shown to be superior to the reflection‐coefficient approximation.

Low-frequency approach to the problem of a horizontal wire antenna above an imperfect ground

The problem of a horizontal wire antenna in the presence of a lossy ground is formulated analytically in terms of electric-field-type (Pocklington-type) integral equation for current distribution on the antenna. This equation is solved numerically by the piecewise sinusoidal Galerkin method. Numerical examples are given. The analysis is restricted to low frequencies.

The wave antenna for transmission and reception

The traveling-wave horizontal-wire antenna over the earth is analyzed in its original form with vertical ground connections (the Beverage antenna) and with these replaced by horizontal terminations. For transmission, the electromagnetic field of an antenna with optimum length is determined, both along the surface of the earth in air and in the earth, in an accurate but simple form that takes full account of the proximity of the earth (lake, sea) on the distribution of current. For reception, the induced currents in the antenna and in the load are determined for a field incident along the surface of the earth. The two types of termination are compared and their contributions shown to be small when the horizontal wire has a length near the optimum.

On the impedance of a long buried horizontal wire antenna

Simple engineering expressions for the external impedance per unit length of a long buried horizontal electric antenna are derived by employing finitely conducting earth image-theory techniques. The results should be applicable to horizontal wire antennas employed in the extremely low frequency (ELF) and very low frequency (VLF) bands.

The horizontal-wire antenna over a dissipative half-space: Generalized formula and measurements

It is shown and verified by experiment that a horizontal resonant or traveling wave antenna placed in air close to a dense halfspace with the properties of lake or sea water or earth behaves like a terminated lossy transmission line. The terminal impedance is related to the radiation of the antenna into the air and the complex wavenumber and characteristic impedance are those of an infinitely long line. The complex wavenumber takes account of both dissipation in and radiation into the dense half-space.