Begell House Inc.
Radio Physics and Radio Astronomy
RPRA
2152-274X
2
2
2011
IDENTIFICATION OF SATURN LIGHTNINGS RECORDED BY THE UTR-2 RADIO TELESCOPE AND CASSINI SPACECRAFT
93-98
10.1615/RadioPhysicsRadioAstronomy.v2.i2.10
V. V.
Zakharenko
Institute of Radio Astronomy, National Academy of Sciences of Ukraine
K. Y.
Mylostna
Institute of Radio Astronomy, National Academy of Sciences of Ukraine, Kharkiv
G.
Fischer
The University of Iowa, Iowa City, Iowa
Alexandr A.
Konovalenko
Institute of Radio Astronomy of the National Academy of Sciences of Ukraine
P.
Zarka
Ovservatoire de Paris-Meudon, Paris, CNRS UMR 8644, LESIA, France
J.-M.
Griebmeier
ASTRON, Dwingeloo, the Netherlands
B. P.
Ryabov
Institute of Radio Astronomy, National Academy of Sciences of Ukraine
Dmitry M.
Vavriv
Institute of Radio Astronomy, National Academy of Sciences of Ukraine 4, Krasnoznamennaya St., Kharkiv 61002, Ukraine
V. B.
Ryabov
Department of Complex Systems, Future University Hakodate, Hakodate, Hokkaido, Japan
H. O.
Rucker
Institut für Weltraumforschung der Österreichischen Akademie der Wissenschaften, 6, Schmiedlstrasse, Graz, 8042, Austria
P.
Ravier
LESI, Université d'Orléans, France
M. A.
Sidorchuk
Institute of Radio Astronomy, National Academy of Sciences of Ukraine, Kharkiv, Ukraine
B.
Cecconi
ASTRON, Dwingeloo, the Netherlands
A.
Coffre
Station de Radioastronomie de Nançay, France
L.
Denis
Station de Radioastronomie de Nançay, France
C.
Fabrice
Station de Radioastronomie de Nançay, France
R. V.
Kozhyn
Institute of Radio Astronomy, National Academy of Sciences of Ukraine 4, Krasnoznamennaya St., Kharkov 61002, Ukraine
D. V.
Mukha
Institute of Radio Astronomy, National Academy of Sciences of Ukraine, Kharkiv, Ukraine
L.
Pallier
ASTRON, Dwingeloo, the Netherlands
J.
Schneider
LUTH Observatoire de Paris-Meudon, France
V. A.
Shevchenko
Institute of Radio Astronomy, National Academy of Sciences of Ukraine
V. V.
Vinogradov
Institute of Radio Astronomy, National Academy of Sciences of Ukraine
R.
Weber
LESI, Université d'Orléans, France
V. S.
Nikolaenko
Institute of Radio Astronomy, National Academy of Sciences of Ukraine, Kharkiv, Ukraine
Saturn Electrostatic Discharges
time difference function
spectrum
storm activity
The Saturn Electrostatic Discharges (SED) simultaneously recorded in the initial period of storm F at the UTR-2 radio telescope and Cassini spacecraft are investigated. The UTR-2 used the FFT-spectral receiver operating 12−33 MHz, while the Cassini the serial spectrum analyzer RPWS (Radio Plasma Wave Science) operating 1.8−16 MHz. The ground-based and space-borne data processed have shown very good agreement. E-folding time of SED and its dependence on episode intensity in the initial period of storm F were determined, too.
RECEIVING COMPLEX FOR SPECTRAL SURVEY WITHIN 85 TO 116 GHZ AT THE CRAO RT-22 RADIO TELESCOPE
99-104
10.1615/RadioPhysicsRadioAstronomy.v2.i2.20
A. V.
Antyufeyev
Institute of Radio Astronomy, National Academy of Sciences of Ukraine
S. Y.
Zubrin
Institute of Radio Astronomy, National Academy of Sciences of Ukraine, Kharkiv, Ukraine
A. M.
Korol
Institute of Radio Astronomy, National Academy of Sciences of Ukraine, Kharkiv, Ukraine
O. M.
Korolev
Institute of Radio Astronomy, National Academy of Sciences of Ukraine, Kharkiv, Ukraine
V. V.
Myshenko
Institute of Radio Astronomy, National Academy of Sciences of Ukraine
4, Mystetstv St., Kharkiv, 61002, Ukraine
V. I.
Piddyachiy
Institute of Radio Astronomy, National Academy of Sciences of Ukraine, Kharkiv, Ukraine
A. V.
Poladich
Institute of Radio Astronomy, National Academy of Sciences of Ukraine, Kharkiv, Ukraine
V. I.
Shkodin
Institute of Radio Astronomy, National Academy of Sciences of Ukraine, Kharkiv, Ukraine
Valery M.
Shulga
Institute of Radio Astronomy of the National Academy of Sciences of Ukraine, Kharkov, Ukraine
millimeter wavelength radiation
spectral observations
radio telescope
maser radiation
galactic radio sources
A receiving complex has been developed for spectral survey of radiation from the galactic radio source molecules within 85−116 GHz using the RT-22 radio telescope of the Crimean Astrophysical Observatory. The complex architecture, possible observation modes and calibration technique are described. Recommendations are given as for application of the available observation modes. Examples of real spectrum and continuum observations are presented.
A SUPER-WIDEBAND BASIC ELEMENT FOR LOW-FREQUENCY ANTENNAS OF RADIO TELESCOPES: PART 1. PRINCIPLES OF REALIZATION
105-113
10.1615/RadioPhysicsRadioAstronomy.v2.i2.30
Alexandr A.
Konovalenko
Institute of Radio Astronomy of the National Academy of Sciences of Ukraine
I. N.
Zhouck
Institute of Radio Astronomy, National Academy of Sciences of Ukraine, Kharkiv, Ukraine
A. A.
Gridin
Institute of Radio Astronomy, National Academy of Sciences of Ukraine, 4, Chervonopraporna St., Kharkiv 61002, Ukraine
V. P.
Bovkoon
Institute of Radio Astronomy, National Academy of Sciences of Ukraine
I. N.
Boobnov
Institute of Radio Astronomy, National Academy of Sciences of Ukraine
radio telescope antenna
coaxial line
horizontally oriented dipole
super-wideband dipole
Discussed in the paper are requirements to the super-wideband basic element of the radio telescope antenna operating below 200 MHz, as well as the principles underlying realization of such passive, short, symmetric, horizontally oriented dipole and possibilities for its matching with the high frequency (h.f.) feed of the telescope’s antenna array. It is shown that, despite the sharp variations of the dipole’s input impedance, it proves possible to obtain, taken the high effective temperature of the celestial sphere, a degree of matching characterized by a SWR lower than 3 over the frequency band 12.5 to 60 MHz. Within this band the antenna sensitivity is not reduced by more than 0.5 dB relative to the value for a fully matched lossless half-wave antenna. The effect is achieved by means of connecting an additional attenuator in series with the input impedance of the antenna’s basic element. As a result, the ohmic component of the input impedance is leveled through the band of 12.5 to 60 MHz. Coaxial line sections with a common central conductor are used as arms of the antenna basic element, which provides for a 0.8 to 1.0 coupling between the line sections (i.e. aperiodic circuits), and a substantially depressed reactive component of the element’s input impedance.
GRAVITATIONAL LENS SYSTEM Q2237+0305 IN 2001−2008: OBSERVATIONS ON MT. MAIDANAK
115-124
10.1615/RadioPhysicsRadioAstronomy.v2.i2.40
V. N.
Dudinov
Institute of Astronomy, V. Karazin National University of Kharkiv; and Institute of Radio Astronomy, National Academy of Sciences of Ukraine
G. V.
Smirnov
Institute of Astronomy, V. Karazin National University of Kharkiv, Ukraine
V. G.
Vakulik
Institute of Astronomy, V. Karazin National University of Kharkiv, and Institute of Radio Astronomy, National Academy of Sciences of Ukraine, Ukraine
A. V.
Sergeev
Institute of Astronomy, V. Karazin National University of Kharkiv, and Institute of Radio Astronomy, National Academy of Sciences of Ukraine, Ukraine
A. E.
Kochetov
Institute of Astronomy, V. Karazin National University of Kharkiv, and Institute of Radio Astronomy, National Academy of Sciences of Ukraine, Ukraine
gravitational lensing
Q2237+0305
multicolor photometry
microlensing
quasar
The multicolor photometry of images of gravitational lens system Q2237+0305 taken in 2001 to 2008 with the AZT-22 1.5 m telescope (Mt. Maidanak, Uzbekistan) is presented, the photometry procedure applied briefly described. Comparison of our photometry results with the OGLE project data has allowed the reduction relation between these sequences of data. The photometry errors have been estimated, these of the OGLE project are shown to be slightly less than those in our measurements. Quantitative assessments are obtained for the relations between the Q2237+0305 system brightness variations produced separately by microlensing events and inherent quasar variability.
SPECTRAL ENERGY DISTRIBUTION SIMULATIONS FOR SUBSTARS WITH GAPLESS DISKS
125-132
10.1615/RadioPhysicsRadioAstronomy.v2.i2.50
O. V.
Zakhozhay
Main Astronomical Observatory, National Academy of Sciences of Ukraine
substars
protoplanetary disks
spectral energy distribution
An algorithm is presented to calculate the spectral energy distributions of substars with gapless disks depending on their geometry, age and angle of observation. 336 spectral energy distributions have been calculated in the systems spaced within 10 pc and consisting of a substar with mass (0.01−0.08)Mʘ , aged 1−30 Myr, and a flat or flared gapless disk observed at angles of 0° to 80° . The emission fluxes from such systems are > 0.001 Jy at wavelengths from 1.7 μ;m to 1 cm, while at wavelengths > 40 μ;m the fluxes from disks, irrespective of angle of observation, are determinant in the total emission of systems.
NEAR-FIELD SCATTERING OF WAVES FROM A STATISTICALLY ROUGH SURFACE: IV. FREQUENCY SPECTRUM IN THE CASE OF OBLIQUE MONOSTATIC RADAR SOUNDING
133-137
10.1615/RadioPhysicsRadioAstronomy.v2.i2.60
A. S.
Bryukhovetsky
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
scattering
statistically rough surface
frequency spectrum
monostatic radar sounding
Results of the previous study are used for determining the frequency spectrum of the field scattered by a "large" statistically rough area. The limiting transition to the well known result is considered. The validity criterion for the obtained solution is presented.
NEAR FIELD-TO-FAR FIELD RELATION IN WAVE BACKSCATTERING BY A STATISTICALLY ROUGH SURFACE
139-154
10.1615/RadioPhysicsRadioAstronomy.v2.i2.70
A. S.
Bryukhovetsky
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine
critical point
stationary phase
asymptotic representation
Fresnel integrals
In the case of wave backscattering by a statistically rough surface, asymptotic representations have been found for the two-fold integrals of rapidly oscillating functions which determine the temporal correlation function of the scattered field. Calculations for grazing angles greatly in excess of the characteristic angular size of the Fresnel zone were performed using the stationary phase method. The obtained solution admits limiting transitions to the values of physical parameters corresponding to the cases of "large" and "small" scattering areas. In the opposite case where grazing angles are much smaller than the Fresnel zone angular size a combined solution has been obtained applying the stationary phase technique with respect to the variable azimuthal angle and the Fraunhofer diffraction approximation with respect to the radial variable. The calculations make it possible to establish relation with the solutions which are based on heuristic simplifying hypotheses.
THE H-MODE DIFFRACTION BY A SLOT SYSTEM IN A COMMON WALL OF TWO PARALLEL RECTANGULAR WAVEGUIDES
155-162
10.1615/RadioPhysicsRadioAstronomy.v2.i2.80
Sergey A.
Pogarsky
V. Karazin National University of Kharkiv, 4 Svobody Sq., Kharkiv 61022, Ukraine
M. E.
Kaliberda
V. Karazin National University of Kharkiv, 4 Svobody Sq., Kharkiv 61022,
Ukraine
rectangular waveguide
directional coupler
singular integral equation
The H-mode diffraction by a system of slots in a common wall of the two rectangular waveguides is solved by the operator method. The consideration is given to rectangular shape slots. The character of waveguide coupling has been examined in different slot sizes and locations to recognize relevant behavioral laws of frequency bands over which the structure performs as a directional coupler and a power divider. The present method results are compared with those available in the literature.
DIFFRACTION OF THE H10 WAVEGUIDE MODE ON A TRANSVERSE SLOT CUT THROUGH THE WIDER WALL OF A RECTANGULAR WAVEGUIDE WITH A LOCALIZED DIELECTRIC INSERT
163-169
10.1615/RadioPhysicsRadioAstronomy.v2.i2.90
L. P.
Yatsuk
V. Karazin National University of Kharkov, 4, Svoboda Square, Kharkov
61077, Ukraine
D. Y.
Penkin
Kharkiv National University of Radio Engineering and Electronics, 14, Lenin Ave, Kharkiv, 61166, Ukraine
slot
waveguide
dielectric
scattering parameters
The H10 mode is scattered from a narrow transverse slot placed over a finite-length dielectric insert completely filling the cross-section of a rectangular waveguide. The magnetic field induced by the slot in the dielectric, directly beneath the slot, is found with the use of the eigenwave technique and the tensorial Green function. Power parameters of the slotted waveguide radiator are determined. Correctness of the mathematical model constructed is confirmed by comparison of the model-based test computations with the results obtained with a commercial simulation code. A possibility has been discovered of ensuring a close to unity radiation efficiency from the slot.
MODE BASIS DERIVATION BY USING INTEGRAL EQUATION TECHNIQUE FOR A CIRCULAR DIELECTRIC WAVEGUIDE
171-180
10.1615/RadioPhysicsRadioAstronomy.v2.i2.100
M. N.
Legenkiy
V. Karazin National University of Kharkiv, 4 Svobody Sq., Kharkiv 61022, Ukraine
dielectric waveguide
mode basis
continuous spectrum
integral equation technique
evolutionary equations
A new approach based on the integral equation technique is proposed for the mode basis derivation of a circular dielectric waveguide in free space. The mode functions and the normalizing functions have been evaluated analytically. The frequency-domain mode expansion in this basis is shown rapidly convergent. The field progress in longitudinal direction and time is described by the system of evolutionary integro-differential equations for the field expansion coefficients. Using the method of moments has shown the capacity of this system reduction to the system of differential matrix equations whose harmonic solution yields dispersion curves of a circular dielectric waveguide. The method is verified by a good agreement between the obtained dispersion curves and the values from known frequency domain solutions.
RADAR CONTRAST OF WIND RIPPLES ON THE SEA WAVE OF SEISMIC ORIGIN
181-188
10.1615/RadioPhysicsRadioAstronomy.v2.i2.110
A. G.
Boev
Institute of Radio Astronomy, National Academy of Sciences of Ukraine
A. A.
Boeva
Kharkiv National Politechnical Institute
O. Y.
Matveyev
Kalmykov Center for Earth Radiophysical Sensing, National Academy of Sciences of Ukraine, and National Space Agency of Ukraine
radar contrast
seismic origin wave
wind ripples
The problem for radar contrast of wind waves in the short gravity and gravity-capillary ranges on the sea surface perturbed by a seismic origin wave is solved. Relations of the radar contrast for the sensing wavelengths 3 cm and 5.66 cm are investigated versus the parameters of seismic wave and sea depth. The possibility for reliable radar detection of the sea seismic wave with very small amplitude in initial stage of its development is shown.
A MICROWAVE TECHNIQUE FOR DETERMINING THICKNESSES OF DIELECTRIC MATERIALS USING RADIATORS WITH SCANNING DIRECTIONAL PATTERNS
189-196
10.1615/RadioPhysicsRadioAstronomy.v2.i2.120
N. L.
Yevich
Podgorny Institute of Mechanical Engineering Problems, National Academy of Sciences of Ukraine
Yu. V.
Prokopenko
O.Ya. Usikov Institute for Radio Physics and Electronics, National Academy
of Sciences of Ukraine, 12 Academician Proskura St., Kharkiv 61085, Ukraine
microwave measurement technique
scanning directional pattern
dielectric materials
permittivity and thickness estimates
measurement errors
Capabilities of microwave metrology are analyzed as for determining thicknesses of planar layers of dielectric nonmagnetic materials placed either on a metal substrate or in free space. The radiating system represents a short-circuited double-arm section of a dielectric waveguide and a dielectric plate electrodynamically coupled with it. Estimates of errors of measuring the thickness and permittivity of the analyzed layer are presented.