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1.
A model of decameter-decimeter radio wave propagation in a strongly inhomogeneous mid-latitude ionosphere is constructed using
a modified method of radio wave refractive scattering. The model establishes the relationship between the basic statistical
radio wave characteristics and the turbulence parameters of the upper ionosphere. Different aspects of the theory of radio
wave refractive scattering are considered in application to the study of amplitude and phase fluctuations of decameter-decimeter
radio waves propagating in a three-dimensional randomly inhomogeneous ionosphere with an arbitrary electron density distribution.
Radiophysical Research Institute, Nizhny Novgorod, Russia. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika,
Vol. 40, No. 11, pp. 1323–1341, November, 1997. 相似文献
2.
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
3.
The possibility of excitation of thermomagnetic instability in the ionospheric F-region with an external DC electric field on exposure to waves from powerful ground-based radio transmissions is discussed. The threshold and growth rate of the instability are determined. It is shown that such instability can appear in local regions with a rather high level of plasma waves and in the high-latitude ionosphere, especially for high ionospheric-plasma drift velocities.Scientific-Research Institute of Radiophysics. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 37, No. 5, pp. 674–679, May, 1994. 相似文献
4.
Yu. Yu. Kulikov V. L. Frolov 《Russian Journal of Physical Chemistry B, Focus on Physics》2013,7(6):692-695
The results of microwave measurements of ozone emission in the middle atmosphere during modification of the ionosphere by high-power short radio waves on March 14–19, 2009 and on March 27–28, 2011. The modification was carried out using a SURA heating facility (Radiophysical Research Institute) in conjunction with two microwave ozonometers aimed at different parts of the sky. A new physical phenomenon of decrease of the intensity of microwave emission from the mesosphere in the ozone line upon the modification of the ionosphere with high-power short radio waves is discovered. 相似文献
5.
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
6.
The results of a complex experiment on the synchronous observation of geostationary-satellite signals and of reflected HF signals of the vertical-sounding station in the course of ionosphere modification by powerful short waves are analyzed using the method of refractive scattering of radio waves. We show that the main statements of the known stochastic theory of F-spread in the ionosphere can be used in the development of a model of artificial F-spread. In particular, the artificial F-spread can be described as multiple-ray propagation of short radio waves in the ionosphere modified by high-power radio waves, the electron-density distribution of which is a random process locally stationary in space and time.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 39, No. 7, pp. 876–881, July, 1996.This paper was supported by the Russian Foundation for Fundamental Research (project 95-02-03716). 相似文献
7.
We consider the features of propagation of decametric radio waves along the transpolar ionospheric paths. The results of recording
round-the-world trip echo signals, which was performed during the many-hour sessions in November and December 1971, are analyzed.
A facility emitting waves at the maximum usable frequency in the zero-azimuth direction and recording the signal arriving
from the opposite direction, which was located in the south of Ukraine, was used. The data obtained on November 23, 1971 for
the radiation frequencies f
o = 16–17 MHz are considered a standard example. We also present the results of calculating the diurnal variation in the maximum
usable frequency of the F
2 layer for a radio-path hop of 4000 km in length in the forward and backward paths Novorossiysk–USA north-west coast in May
1980, which were obtained by the standard methods and correspond to the experimental data. It is shown that the obtained data
can be interpreted on the basis of radiophysical phenomena, namely, (i) the formation of a grazing radio wave near the top
of the first hop with a length of 3000–4000 km for the radiation at the maximum usable frequency and (ii) the night-time retaining
of the daytime properties of the F
2 region in the case of oblique heating by a high-power radio wave. The performed study allowed us to estimate the possibility
of the Alaska HAARP facility to emit to the territory of the Russian Federation.
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 52, No. 2, pp. 118–127, February 2009. 相似文献
8.
A. V. Kostrov V. V. Nazarov M. V. Starodubtsev 《Radiophysics and Quantum Electronics》2008,51(11):890-903
We present the results of laboratory modeling of the physical processes which lead to smallscale stratification of the ionospheric
plasma during active experiments on modification of the ionosphere by high-power radio waves. It is shown that such a stratification
can result from thermal self-channeling of Langmuir waves in a magnetoplasma. We established that the selfchanneling is threshold
in behavior such that the threshold significantly increases near gyroharmonics. It is demonstrated that in the process of
self-channeling, the frequency spectrum of the Langmuir wave is enriched. In particular, spectral maxima are formed, which
are shifted away from the carrier frequency by a value of the order of the lower-hybrid frequency.
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 51, No. 11, pp. 988–1003, November 2008. 相似文献
9.
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.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 50, No. 8, pp. 695–708, August 2007. 相似文献
10.
G. G. Vertogradov V. P. Uryadov V. G. Vertogradov 《Radiophysics and Quantum Electronics》2007,50(1):1-7
We present the results of the ionosphere oblique chirp sounding on the Cyprus—Nizhny Novgorod, Cyprus—Rostov-on-Don, and Moscow—Rostov-on-Don
mid-latitude paths during X-ray flares in January 17, 19, and 20, 2005. It is found that during strong flares the blackout
of short radio waves was observed over the entire frequency range of chirp sounding on the Cyprus—Nizhny Novgorod and Cyprus—Rostov-on-Don
paths. Modeling of the electron-density profiles in the lower ionosphere based on absorption of short radio waves on the Moscow—Rostov-on-Don
path at different stages of the decay of the X-ray radiation intensity is carried out. It is shown that at the instant corresponding
to the maximum value of the flare radiation flux, the electron density in the lower ionosphere at altitudes 60–80 km increased
by a factor of about 10 and 100 for flares with radiation flux densities 5·10−2 and 3·10−1
erg/(cm
2·s) in the wavelength range 0.5–4.0 Å which took place in January 19 and 20, respectively.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 50, No. 1, pp. 1–8, January 2007. 相似文献
11.
We consider the problem of diagnostics of the local structure of small-scale ionospheric turbulence using the multifractal
analysis of received signals from the Earth’s orbital satellites after the radio sounding of the inhomogeneous ionosphere
by these signals. In particular, it is shown that analysis of the multifractal structure of the received-signal amplitude
records by the method of multidimensional structural functions allows one to determine the indices of the multipower local
spectra of the small-scale ionospheric turbulence, which are inherent in it due to the nonuniform spatial distribution of
small-scale fluctuations of the electron number density. It is noted that information on the multipower spectrum of small-scale
ionospheric turbulence is not available for the conventional radio scintillation method based on the classical spectral analysis
of received signals during the remote radio sounding of the ionosphere. At the same time, the method of multidimensional structural
functions is efficient under conditions of actual nonstationarity of the process of scattering of the HF radio waves by the
randomly inhomogeneous ionospheric plasma. The method of multidimensional structural functions is used for the multifractal
processing of received signals of orbital satellites during special experiments on radio sounding of the midlatitude ionosphere
under natural conditions and its modification by high-power HF radio waves. First data on the indices of the multipower local
spectra of small-scale ionospheric turbulence are obtained.
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 52, No. 1, pp. 14–22, January 2009. 相似文献
12.
We consider the features of the modification of the equatorial ionosphere by high-power radiowaves. A possibility for creating
strong (compared to mid-latitude) quasi-periodic ionospheric F-layer irregularities, formed by the field of the high-power
standing wave, producing artificial bubbles, and influencing the natural equatorial “bubbles” is discussed. The peculiarities
of exciting the striction and thermal parametric instabilities in the equatorial ionosphere are considered. The problem of
the modulation of the equatorial current jet is briefly discussed.
Radiophysical Research Institute, Nizhny Novgorod, Russia; Swedish Institute of Space Physics, Uppsala Division, Uppsala,
Sweden. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 40, Nos. 1–2, pp. 250–262, January–February,
1997. 相似文献
13.
G. G.Vertogradov V. P. Uryadov E. G. Vertogradova A. A. Ponyatov 《Radiophysics and Quantum Electronics》2010,53(3):161-170
We present the results of experimental studies of propagation of short radio waves on a long transequatorial path of Laverton
(Australia) — Rostov-on-Don, which were obtained with the help of an ionosonde/direction finder with chirp modulation of the
signal. It is shown that conditions for propagation of anomalous signals by means of sideband reflection of radio waves from
the Himalayan Hills and the Plateau of Iran and also due to scattering of radio waves from the high-latitude ionosphere of
the northern hemisphere are realized on the given path. The propagation of radio waves is modeled with allowance for their
scattering by anisotropic magnetic field-aligned irregularities of a high-latitude ionosphere, which are located on the northern
wall of the main ionospheric trough of the F layer. It is shown that the results of the experiment agree well with the calculated data. 相似文献
14.
S. M. Grach E. N. Sergeev V. A. Yashnov P. V. Kotov 《Radiophysics and Quantum Electronics》2008,51(7):499-514
Alternative mechanisms of generation of the stimulated electromagnetic emission (SEE) excited in the ionosphere by high-power
radio waves are analyzed on the basis of measurements of the SEE spectra obtained during the pump-wave frequency sweeping
near the forth (n = 4) and fifth (n = 5) harmonics of the electron gyrofrequency nfce [1] and their comparison with the existing physical models. A method for determination of the magnetic field strength and plasma
density near the double-resonance region in the ionosphere is developed. It is shown that the generation of the broad upshifted
maximum (BUM) feature in the SEE spectrum should occur several kilometers below the double-resonance altitude. A role of high-frequency
plasma modes and small-scale magnetic field-aligned irregularities, excited under ionosphere pumping by a high-power radio
wave, in the formation of SEE spectra is demonstrated. It is shown that the difference in the emission intensities for f0 ≲ nfce and f0 > nfce is related to different regions (altitudes) at which the plasma waves exist in these cases.
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 51, No. 7, pp. 553–570, July 2008. 相似文献
15.
We report on the results of studying the lower ionosphere by a method based on the resonant scattering of radio waves by artificial
periodic inhomogeneities of the ionospheric plasma. Different aspects of studying the sporadic E layer such as the influence of the vertical transfer on its formation, the possibility of examination of its ion composition,
and the influence of the ionosphere heating on the layer characteristics are discussed. The results of determining the parameters
of the E
s layer and some characteristics of the lower ionosphere during the creation of artificial periodic inhomogeneities at two
frequencies are presented.
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 51, No. 11, pp. 956–969, November 2008. 相似文献
16.
L. F. Chernogor V. L. Frolov G.P. Komrakov V. F. Pushin 《Radiophysics and Quantum Electronics》2011,54(2):75-88
We present the results of spectral analysis of temporal variations in the Doppler frequency shift of the ionosphere-reflected
signals from a high-frequency vertical ionospheric sounding radar located near the city of Kharkov in the days of exposure
of the ionospheric plasma to the high-power radio emission of the Sura facility (Nizhny Novgorod) and in the reference day
in the absence of such an exposure. It was established that the spectral characteristics of quasiperiodic variations in the
Doppler frequency shift in the range of periods 10–60 min in the days of work of the facility and in the reference day differed
significantly. This is considered as evidence in favor of the generation (amplification) of acoustic–gravity waves propagating
at the ionospheric altitudes by high-power periodic high-frequency radiation of the Sura facility. 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.
V. L. Frolov D. I. Nedzvetsky G. P. Komrakov 《Radiophysics and Quantum Electronics》2005,48(9):661-672
We present the results of measuring the characteristics of the stimulated electromagnetic emission (SEE) of the ionosphere
with variation in the zenith angle of a pump beam of high-power O-mode radio waves in the geomagnetic-meridian plane. The
experiments were performed at the midlatitude heating facility “Sura.” It is established that the maximum intensity of the
DM and BC components of SEE is observed for southward inclination angles θ ≈ 8°--12° of the antenna beam, for which the most
intense generation of artificial small-scale ionospheric irregularities also takes place. Based on the results of measurements
near the fourth and fifth harmonics of the electron gyrofrequency, it is found that the first component of the BUM (BUM-1)
is generated only when the pump wave reaches the plasma-resonance region. This allows one to assume that, unlike the second
component of the BUM (BUM-2), whose generation is determined by development of instability in the upper-hybrid resonance region,
the BUM-1 generation mechanism should be related to processes of interaction between a high-power radio wave and the plasma
in the plasma-resonance region.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 48, No. 9, pp. 743–756, September 2005. 相似文献
19.
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
20.
We consider the efficiency of trapping of short plasma waves excited by a high-power radio wave inside the magnetic field-aligned
small-scale cylindrical irregularities with low density. It is shown that in the case of cylindrical irregularities the reflection
of a plasma wave from the points of its transformation into cold plasma oscillations is sufficiently large. Therefore, this
process must be taken into account in the calculation of heating of irregularities in the field of a high-power radio wave.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 50, No. 3, pp. 181–195, March 2007. 相似文献