WorldCat Identities

ARCO POWER TECHNOLOGIES INC WASHINGTON DC

Overview
Works: 7 works in 7 publications in 1 language and 7 library holdings
Publication Timeline
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Most widely held works by ARCO POWER TECHNOLOGIES INC WASHINGTON DC
Artificial Ionospheric Mirrors for Radar Applications( Book )

1 edition published in 1990 in English and held by 1 WorldCat member library worldwide

Recognition of performance limitations associated with traditional skywave over-the-horizon (OTH) high frequency (HF) radars has led a number of investigators to propose the creation of an Artificial Ionospheric Mirror (AIM) in the upper atmosphere, in order to reflect ground-based radar signals for OTH surveillance. The AIM is produced by beaming sufficient electromagnetic Power to the lower ionosphere (around 70 km) to enhance the in situ ionization level to 107 108 electrons/cm3, thereby providing an ionized layer capable of reflecting radar frequencies of 5 - 90 MHz. This paper presents a baseline AIM system concept and an associated performance evaluation, based upon the relevant ionization and propagation physics and in the context of air surveillance for the cruise missile threat. Results of the subject study indicate that a system using this concept would both complement and enhance the performance of the existing skywave OTH radars
Physics of RF Breakdown for AIM Applications( Book )

1 edition published in 1990 in English and held by 1 WorldCat member library worldwide

Both a simple lest particle approach and a complete kinetic calculation are used to predict the net electron production rate of an RF signal under conditions appropriate for an Artificial Ionospheric Mirror (AIM) system These predictions are compared with each other and with experimental data and found to be in good agreement. The test particle based formula is incorporated into a model which calculates the one-dimensional vertical electron density profile created by a ground-based RF heater, and the performance of a baseline heater design is investigated, providing the foundation for the specification of a baseline AIM heater system
Electrojet Modulation ELF Communications( Book )

1 edition published in 1990 in English and held by 1 WorldCat member library worldwide

Me causes for the inefficient conversion of HF to ELF waves by ionospheric heating observe in recent experiments are examined. It is found that for the low frequency HF range 2.5-4 MHz used in the present experiments the modified conductance saturates during a fraction of the HF irradiation cycle. As a result most of the HF energy is transferred to processes that do not affect the conductance significantly. This was experimentally confirmed using the HIPAS facility. Techniques relying on fast HF antenna sweeping by which the efficiency can increase by more than two orders of magnitude are presented
ELF/VLF Generation( )

1 edition published in 1991 in English and held by 0 WorldCat member libraries worldwide

A preliminary analysis of the results of the ELF experimental campaigns conducted in the May - September 1990 time frame using the HIPAS transmitter in conjunction with the UCLA ELF receiver at the NOAA site and the mobile NUSC receiver is presented. Following a discussion of the critical physics issues and scalings relating to practical implementation of ionospherically generated ELF to submarine communications, the results of the two campaigns are presented. The data show conclusively that the measured ELF are low frequency signals generated by modulated ionospheric currents and not by nonlinear interference effects of the modulated HF. For the HIPAS parameters the received ELF signals are consistent with an equivalent Horizontal Magnetic Dipole (HMD) located at an altitude of 75 km radiating with an average dipole moment M 6x10 to the 8th power A-m sq. The maximum M value achieved during the campaign was 9x10 to the 8th power A-m sq. Results related to conversion efficiency scaling with HF polarization, low duty and painting operation, ELF frequency and ionospheric conditions, along with suggestions for future studies are also presented
Electromagnetic wave reflection from irregular plasma layers by Konstantinos Papadopoulos( )

1 edition published in 1993 in English and held by 0 WorldCat member libraries worldwide

The general theory describing reflection of electromagnetic waves from irregular reflectors was formulated by using path integral techniques (Dashen, 1979; Flatte, 1979). The general formulae reproduce the well known reflection coefficients for wave scattering from random rough surfaces derived by using Kirchhoff's theory or perturbation theory (Ogilvie, 1991). The theory was used to determine the degradation of an OTH radar signal scattered from irregular Artificial Ionospheric Mirrors (AIM). The cases of density irregularities induced by fluctuations in the ambient neutral density and by fluctuations in the heater power were separately examined. Scaling laws and bounds for minimal signal loss were derived
Physics Studies in Artificial Ionospheric Mirror (AIM) Related Phenomena( )

1 edition published in 1990 in English and held by 0 WorldCat member libraries worldwide

This document reports on the progress made and final results of a study into the fundamental physics of electromagnetic induced ionization in the lower ionosphere (60 - 80 km), using a ground based radiation source. The technique of remotely controlled ionization can be used to create a layered region of ionization and to then use the Artificial Ionospheric Mirror (AIM) to reflect HF/VHF signals for over the horizon communications and radar applications. The objective of the study was to identify the basic physics issues controlling RF breakdown phenomena and to develop an understanding of those issues sufficient for performing quantitative prediction of AIM characteristics and the impact of those characteristics on the reflecting wave. Results of the study indicate that AIM is a viable concept and has the potential of providing important benefits over more traditional communication/radar technology
System Concept and Analysis of an Artificial Ionospheric Mirror (AIM) Radar( )

1 edition published in 1990 in English and held by 0 WorldCat member libraries worldwide

Recognition of performance limitations associated with traditional skywave over-the-horizon (OTH) high frequency (HF) radars has led a number of investigators to propose the creation of an Artificial Ionospheric Mirror (AIM) in the upper atmosphere, in order to reflect ground-based radar signals for OTH surveillance. The AIM is produced by beaming sufficient electromagnetic power to the lower ionosphere (around 70 km) to enhance the in situ ionization level to 10 to the 7th power - 10 to the 8th power electrons/cu cm, thereby providing an ionized layer capable of reflecting radar frequencies of 30 - 90 MHz. This paper presents a baseline AIM system concept and an associated performance evaluation, based upon the relevant ionization and propagation physics and in the context of air surveillance for the cruise missile threat. Results of the subject study indicate that a system using this concept would both complement and enhance the performance of the existing skywave OTH radars
 
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