共查询到20条相似文献,搜索用时 46 毫秒
1.
V. L. Frolov V. O. Papoport G. P. Komrakov A. S. Belov G. A. Markov M. Parrot J. L. Rauch E. V. Mishin 《Radiophysics and Quantum Electronics》2008,51(11):825-833
We report on the French DEMETER and American DMSP satellite measurements of largescale field-aligned plasma-density perturbations
(ducts) induced in the topside ionosphere by the ionospheric F
2-layer pumping by means of high-power HF radio waves from the “Sura” heating facility. Characteristics of such plasma perturbations
and conditions of their formation are determined.
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 51, No. 11, pp. 915–924, November 2008. 相似文献
2.
We present the results of new studies of the sporadic E layer in the case of heating of the ionosphere by high-power HF radio
emission. The measurements were performed at the “Sura” heating facility. Ionosphere was modified by high-power radio emission
from the “Sura” facility and was sounded by the probing radio waves of the same frequency and mode. The heating of the ionosphere
resulted in the formation of artificial periodic inhomogeneities, and an increase in the intensity of all signals scattered
by the D, E, and F regions and the sporadic E layer by 5–20 dB was observed. The increase was observed during heating of the
ionosphere by each magnetoionic component, but was smaller for heating by an ordinary-mode wave. This effect was resonant
and disappeared as a result of the frequency detuning down to 85 kHz. During the ionospheric modification, the signal-intensity
increased due to modulation of the natural profile of the electron number density by the artificial periodic structure.
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Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 50, No. 8, pp. 695–708, August 2007. 相似文献
3.
V. L. Frolov G. P. Komrakov V. E. Kunitsyn A. M. Padokhin A. E. Vasiliev G. A. Kurbatov 《Radiophysics and Quantum Electronics》2010,53(7):379-400
We present the results of experimental studies of the properties of the plasma-density disturbances created during heating
of the ionospheric F2 region by high-power HF radio waves radiated by the “Sura” heating facility (Radiophysical Research Institute, Nizhny Novgorod).
These experiments are specific in that they were performed in a sunlit (daytime) ionosphere when the generation of ionospheric
turbulence has specific features and the turbulence intensity level is low enough. The plasma-density disturbances induced
by high-power HF radio emission were sounded by signals of the GPS satellites, the line of sight to which crossed different
parts of the disturbed ionosphere region. Threshold powers of the excitation of artificial plasma-density variations as well
as spatial, temporal, spectral, and energy characteristics of the generated disturbances are determined. 相似文献
4.
A. A. Ponyatov V. P. Uryadov V. A. Ivanov D. V. Ivanov A. G. Chernov V. V. Shumaev Yu. N. Cherkashin 《Radiophysics and Quantum Electronics》1999,42(4):269-277
We present the results of experimental studies of the influence of artificial ionospheric disturbances on HF signals used
for oblique sounding of the disturbed volume. The measurements have been performed by a chirp ionosonde over the path Yoshkar-Ola-“Sura”-niznhy
Novgorod with length 234 km. We found the 2F2 mode to disappear (attenuation up to 20 dB) when the ionosphere is influenced
by a vertical powerful radiation in the ordinary mode with long (15 min each) heating and pause intervals. Modeling of the
observed effect was carried out. The calculations agree well with experimental data if the traveling ionospheric disturbances
(TID) with vertical and horizontal scales lz∼20 km and lx∼50 km, respectively, and the relative disturbance of the electron density δN∼0.2–0.3 are amplified (generated) during the
ionosphere heating.
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 42, No. 4, pp. 303–313, April 1999. 相似文献
5.
V. V. Belikovich N. V. Bakhmet’eva V. N. Bubukina V. D. Vyakhirev E. E. Kalinina G. P. Komrakov A. V. Tolmacheva 《Radiophysics and Quantum Electronics》2008,51(6):431-437
We present the first results of determining the electron number density in the ionospheric E region by a novel technique based on the creation of artificial periodic irregularities when the ionosphere is affected by
powerful radio emission at two frequencies. Using the results of the measurements performed in October 2006 during heating
of the ionosphere by the “Sura” facility radiation at frequencies 4.7 and 5.6 MHz, we obtained the electron number density
profiles in an altitude range of 100 to 110 km. Features of the procedure of measurement and calculation of the electron number
density are described in detail. It is shown that the method can be used for a study of the irregular structure of the lower
ionosphere.
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Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 51, No. 6, pp. 477–484, June 2008. 相似文献
6.
V. A. Alimov F. I. Vybornov E. N. Myasnikov A. V. Rakhlin 《Radiophysics and Quantum Electronics》2008,51(11):874-879
We show the results of the first experimental studies of the multifractal structure of the developed artificial ionospheric
turbulence. As a result of the special multifractal analysis of the recorded amplitudes of signals from the orbital satellites,
which were obtained during the experiments on radio tomography of the irregularities excited in the ionosphere by the powerful
mid-latitude heating facility “Sura,” it is found that the characteristic multifractal structure of these records is caused
by the nonuniform spatial distribution of the small-scale fluctuations of the electron number density in the artificial irregularities
of the ionospheric plasma. Comparative analysis is performed for the multifractal spectra of fluctuations of both the amplitudes
and energies of signals received from the orbital satellites upon radio transmission probing of the region of artificial ionospheric
turbulence by these signals at three observation points located near the “Sura” heating facility and spaced apart to a distance
of about 100–150 km.
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 51, No. 11, pp. 970–976, November 2008. 相似文献
7.
N. V. Bakhmet’eva V. V. Belikovich M. N. Egereva A. V. Tolmacheva 《Radiophysics and Quantum Electronics》2010,53(2):69-81
We present new results of studying the artificial periodic irregularities produced in the ionosphere by the radio emission
of the high-power heating facility “Sura” during the period of observations of the sporadic E layer. Basing on the measurement results for the velocity of the vertical plasma motion and the electron profile density
in the E region of the ionosphere, which were obtained by the method of resonance scattering of radiowaves by an artificially produced
periodic structure, we analyze the possibility to produce a sporadic E layer by driving metal ions affected by the vertical shear of the velocity, which occurs at these altitudes due to the propagation
of internal gravity waves. The parameters of these waves are evaluated, as well as the mass and concentration of metal ions
in the sporadic E layer. 相似文献
8.
N. V. Bakhmet'eva V. V. Belikovich L. M. Kagan A. A. Ponyatov A. V. Tolmacheva M. C. Kelley M. J. Nicolls 《Radiophysics and Quantum Electronics》2005,48(9):673-685
We present the results of studying the lower ionosphere in 2000–2004 at the “Sura” heating facility by the method of resonance
scattering of radio waves from artificial periodic inhomogeneities of the ionospheric plasma. Experimental data on a study
of the sunset–sunrise phenomena in the ionospheric D region and the possibility of determining the concentrations of atomic
oxygen and excited molecular oxygen are discussed. The results of studying the sporadic layers of ionization are presented
and the method for a study of ion composition of the Es layer is discussed. Data of the August 2004 experiments on a study of the influence of heating the ionosphere on the Es layer and characteristics of artificial periodic inhomogeneities are presented. Prospects for further research are discussed.
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Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 48, No. 9, pp. 757–771, September 2005. 相似文献
9.
N. F. Blagoveshchenskaya T. D. Borisova V. A. Kornienko A. S. Janzhura A. S. Kalishin T. R. Robinson T. K. Yeoman D. M. Wright L. J. Baddeley 《Radiophysics and Quantum Electronics》2008,51(11):847-857
We present the results of experimental studies of specific features in the behavior of small-scale artificial field-aligned
irregularities (AFAIs) and the DM component in the spectra of stimulated electromagnetic emission (SEE). Analysis of experimental
data shows that AFAIs in the polar ionosphere are generated under different background geophysical conditions (season, local
time, the presence of sporadic layers in the E region, etc.). It is shown that AFAIs can be excited not only in the F region, but also in “thick” sporadic E
s layers of the polar ionosphere. The AFAIs were observed in some cycles of heating when the HF heater frequency exceeded the
critical frequency by 0.3–0.5 MHz. Propagation paths of diagnostic HF radio waves scattered by AFAIs were modelled for geophysical
conditions prevailing during the SPEAR heating experiments. Two components, namely, a narrow-banded one with a Doppler-spectrum
width of up to 2 Hz and a broadband one observed in a band of up to 20 Hz, were found in the sporadic E
s layer during the AFAI excitation. Analysis of the SEE spectra shows that the behavior of the DM component in time is irregular,
which is possibly due to strong variations in the critical frequency of the F
2 layer from 3.5 to 4.6 MHz. An interesting feature observed in the SPEAR heating experiments is that the generation of the
DM component was similar to the excitation of AFAIs when the heater frequency was up to 0.5 MHz higher than the critical frequency.
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 51, No. 11, pp. 939–950, November 2008. 相似文献
10.
V. L. Frolov V. V. Chugurin G. P. Komrakov N. A. Mityakov E. N. Myasnikov V. O. Rapoport E. N. Sergeev V. P. Uryadov F. I. Vybornov V. A. Ivanov V. V. Shumaev A. M. Nasyrov I. A. Nasyrov K. M. Groves 《Radiophysics and Quantum Electronics》2000,43(6):446-468
Experimental studies of the features of artificial ionospheric turbulence was performed at the “Sura” heating facility in
August 1998 using numerous diagnostic tools, such as scintillation, chirp-sounding, backscattering, and stimulated electromagnetic
emission (SEE) measurements, as well as sounding a HF-disturbed volume (DV) by probing waves. It has been found that generation
of strong artificial large-scale irregularities (ALSIs), which manifest themselves through the F-spread on ionograms, scintillations
of the satellite signal propagated through the DV, and amplitude fluctuations of the probing wave sounding the DV, is observed
not only for an overdense heating, at fo≤foF2, but also at higher frequencies fo>foF2≥f
uh
(here fo is the pump-wave frequency, foF2 is the critical frequency of the F2-layer for O-mode electromagnetic wave, and f
uh
is the plasma frequency at the upper-hybrid resonance height). This means that transfer of the pump-wave energy in the plasma
due to the development of thermal parametric (resonance) instability, rather than thermal self-focussing instability, plays
the key role in the ALSI generation in the case where the O-mode HF wave is used for the overdense heating. This conclusion
is also confirmed by the fact that the ALSI generation is suppressed in the gyroharmonic frequency range, which is similar
to the well-studied quenching of the downshifted maximum (DM) in SEE spectra. In this paper, we discuss new ALSI features
revealed by the measurements, as well as the limits by which one can control the ALSI spectrum using complex pumping schemes.
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 43, No. 6, pp. 497–519, June, 2000. 相似文献
11.
V. A. Alimov F. I.Vybornov E. N. Myasnikov A. V. Rakhlin V. L. Frolov 《Radiophysics and Quantum Electronics》2009,52(9):609-617
We present the results of the experiment on studying the multifractal structure (with inhomogeneity sizes from tens to hundreds
of meters across the Earth’s magnetic field) of the artificial ionospheric turbulence when the midlatitude ionosphere is affected
by high-power HF radio waves. The experimental studies were performed on the basis of the “Sura” heating facility with the
help of radio sounding of the disturbed region of the ionospheric plasma by signals from the Earth’s orbital satellites. The
influence of the magnetic zenith effect on measured multifractal characteristics of the small-scale artificial turbulence
of the midlatitude ionosphere was examined. In the case of vertical radio sounding of the disturbed ionosphere region, the
measured multipower and generalized multifractal spectra of turbulence coincide well with similar multifractal characteristics
of the ionospheric turbulence under natural conditions. This result is explained by the fact that the scattering of signals
by weak quasi-isotropic small-scale inhomogeneities of the electron number density in a thick layer with a typical size of
several hundred kilometers above the region of reflection of high-power HF radio waves gives the major contribution to the
observed amplitude fluctuations of received signals. In the case of oblique sounding of the disturbance region at small angles
between the line of sight to the satellite and the direction of the Earth’s magnetic field, the nonuniform structure of the
small-scale turbulence with a relatively narrow multipower spectrum and small variations in the generalized multifractal spectrum
of the electron number density was detected. Such a fairly well ordered structure of the turbulence is explained by the influence
of the magnetic zenith effect on the generation of anisotropic small-scale artificial turbulence in a thin layer having a
typical size of several ten kilometers and located below the pump-wave reflection height in the upper ionosphere. 相似文献
12.
N. A. Mityakov G. P. Komrakov Yu. A. Sazonov 《Radiophysics and Quantum Electronics》2008,51(10):750-755
We developed and tested a new method for increasing the effective ionosonde power by 20–40 dB, which uses the transceiving
antenna of the “Sura” facility. Three sections of this antenna were employed as the receiving antenna of the ionosonde in
the test experiments of July 2007. Fine features indiscernible in normal ionosonde mode are distinctly seen in the ionograms.
Different variants of connection of the “Sura” antenna sections to the receiver and transmitter of the ionosonde are considered
and the possibility of simultaneous operation of the “Sura” high-power transmitter and the ionosonde is analyzed.
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 51, No. 10, pp. 830–836, October 2008. 相似文献
13.
We present the results of analysis of the spectra of amplitude scintillations at a frequency of 150 MHz and a difference phase
at frequencies of 150 and 400 MHz, which were obtained in the experiment on radio tomography of artificial ionospheric turbulence
(AIT) excited by the mid-latitude high-power “Sura” heating facility [1]. We used the data on radio probing of the AIT region
at a frequency of 150 MHz by signals from artificial satellites in near-polar circular orbits at altitudes of 1000 km above
the Earth’s surface. The signals were received simultaneously at three spaced apart points located at distances of about 100–150
km from each other along the projection of the satellite trajectory onto the Earth’s surface. The analysis of the data shows
that in the range of scales smaller than 0.5–1.0 km across the geomagnetic field, the AIT spatial spectrum can be described
by the power-law function with the spectral index p⊥ = 1.7–2.5. For irregularities with the same transverse scales, the spectral index in the direction of the magnetic field
amounts to p‖ = 5–7.
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Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 50, No. 8, pp. 722–730, August 2007 相似文献
14.
V. A. Zinichev G. P. Komrakov N. A. Mityakov V. O. Rapoport N. A. Ryzhov Yu. A. Sazonov 《Radiophysics and Quantum Electronics》2009,52(2):117-121
We present the results of first experiments on radio-acoustic sounding of ionosphere at the altitudes from 70 to 85 km. The
sounding was performed in autumn 2006, using a horn acoustic emitter and a radar on the basis of the “Sura” facility. The
emitter had an acoustic power of about 1 kW and operated in the chirp-modulation regime with frequency variation from 15.9
to 18.4 Hz. The radar transmitter operated in the pulse regime at a frequency of 9 MHz and had an average power of 30 kW.
The power of the radio signal scattered from a sound wave in the ionosphere did not exceed 10−16 W, and the measured values of the temperature in the scattering region ranged from 190 to 225 K.
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 52, No. 2, pp. 128–133, February 2009. 相似文献
15.
V. A. Alimov F. I. Vybornov L. M. Erukhimov G. P. Komrakov N. A. Mityakov A. V. Rakhlin 《Radiophysics and Quantum Electronics》1997,40(6):456-458
We show some results of experiments on synchronous sounding of the ionosphere by short-wave signals at the Radiophysical Research
Institute’s test site in Zimenki and Vasil’sursk, Nizhniy Novgorod province, during ionospheric modification by high-power
short radiowaves from transmitters of the “Sura” facility in Vasil’sursk. In the course of experiments we proved directly
the decisive role of large-scale inhomogeneities of the ionospheric plasma with dimensions of from several kilometers to several
dozens of kilometers in the formation of artificial F- spread. The small-scale inhomogeneities with dimensions smaller than
1 km, which are localized in a relatively thin layer near the reflection level of a high-power short radiowave, emerged only
at sounding waves, propagating (reflected) in the immediate vicinity of the center of the heating region.
Radiophysical Research Institute, Nizhny Novgorod, Russia. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika,
Vol. 40, No. 6, pp. 688–692, June, 1997. 相似文献
16.
G. A. Markov A. S. Belov V. L. Frolov V. O. Rapoport M. Parrot J. L. Rauch M. T. Rietveld 《Radiophysics and Quantum Electronics》2008,51(11):834-841
We present the results of measuring the characteristics of electromagnetic and plasma perturbations at the altitudes of the
Earth’s outer ionosphere, which were obtained by the onboard equipment of the French microsatellite DEMETER when it passed
through the magnetic flux tube based on a region modified by high-power HF radio emission of the EISCAT heating facility.
Physical mechanisms which allow one to explain the observed phenomena are considered.
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 51, No. 11, pp. 925–933, November 2008. 相似文献
17.
V. P. Burmaka I. F. Domnin V. P. Uryadov L. F. Chernogor 《Radiophysics and Quantum Electronics》2009,52(11):774-795
We describe the results of using the incoherent scatter technique to observe time-altitude variations in regular parameters
of the ionospheric plasma and wave disturbances, which accompanied periodic modification of the near-Earth plasma by radio
waves emitted by the “Sura” facility. A distinctive feature of the experiments was that the processes in the ionosphere were
diagnosed at a distance of about 1000 km from the facility. It was found that the spectrum composition of wave disturbances
in the electron density was changing noticeably during the active experiment. Quasi-periodic processes in the ionosphere were
observed with a delay of about 40–60 min. The relative amplitude of wave disturbances was equal to 0.02–0.10, and the periods
were equal to 30, 60, 120, and 150–180 min. The observed effect can be explained by the generation and/or amplification of
traveling ionospheric disturbances. The results of theoretical estimations agree well with the observational data. 相似文献
18.
We present a short review of the features of the main components (DM, UM, NC, BC, BUM, and BUS) of stimulated electromagnetic
emission (SEE). We discuss variations of these components in the case where additional X-mode heating is used. The experiments
were performed at the “Sura” heating facility (Nizhny Novgorod, Russia) during the last few years.
Radiophysical Research Institute (NIRFI), Nizhny Novgorod, Russia. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii,
Radiofizika, Vol. 42, No. 7, pp. 635–640, July 1999. 相似文献
19.
V. P. Uryadov G. G. Vertogradov V. G. Vertogradov A. A. Ponyatov V. L. Frolov 《Radiophysics and Quantum Electronics》2004,47(9):646-661
We present the results of radar observations of artificial ionospheric turbulence (AIT) created due to modification of the ionosphere by high-power radio emission from the Sura heating facility (Nizhny Novgorod region, Russia). Measurements were carried out in August 18–22, 2003 in the evening time (16:00–20:00 UT) with the use of over-the-horizon chirp HF radars on the Khabarovsk-Rostov-on-Don, Irkutsk-Rostov-on-Don, Inskip (England)-Rostov-on-Don paths, and also on the Moscow-Rostov-on-Don path for which reference signals of the standard-time RVM station were received. It is found that conditions for propagation of HF signals through the upper ionosphere at frequencies exceeding the maximum usable frequency for standard hop propagation through the F region were realized on the Irkutsk-Sura path in the presence of the powerful sporadic Es layer. The presence of such signals was revealed at the Rostov-on-Don station by receiving radio waves which escape from the altitudes of the ionospheric F region due to scattering by artificial small-scale magnetic-field-aligned irregularities. We studied the ionospheric effects of a magnetic storm occurring during the experiment by using the measurement data of the Doppler frequency shift of signals scattered by artificial ionospheric turbulence. It is shown that during a magnetic storm, the electric field and the drift velocity of irregularities at the altitudes of the F layer over the Sura facility reach values of 8.6 mV/m and 186 m/s, respectively, which are typical of the high-latitude ionosphere. We consider the relation between quasi-periodic oscillations of the Doppler frequency shift of the scattered signal and propagation of magnetohydrodynamic waves excited during the magnetospheric storm.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 47, No. 9, pp. 722–738, September, 2004. 相似文献
20.
V. A. Zinichev G. P. Komrakov N. A. Mityakov V. O. Rapoport 《Radiophysics and Quantum Electronics》2009,52(1):20-23
We present the results of the vertical ionosphere sounding at a frequency of 9.02 MHz using the “Sura” facility. Intense backscatter
signals from meteor trails were observed at altitudes 100–130 km. Increased background of the scattered signal, which was
about − 100 dB with respect to the mirror-reflected signal, was observed at altitudes of about 190–200 and 270–280 km. According
to the Doppler-shift measurements of the scattered-signal frequency, the wind velocity was more than 30 m/s at altitudes 100–130
and 270–280 km and was significantly smaller in the altitude range 190–200 km.
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 52, No. 1, pp. 23–27, January 2009. 相似文献