1998, volume 3, № 3

THE UHF THREE-COORDINATE RADAR WHICH WAS THE FIRST TO BE DEVELOPED IN THE USSR IN KHARKOV

A. A. Kostenko, А. I. Nosich

7-32

The foundation of the Kharkov radiophysical school and the development work on radio location, which was carried out in the former Soviet Union, have been outlined in a historical review describing the development of the first UNF three-coordinate radar at the Ukrainian Physics-Technical Institute in late 30 s. The paper contains the reminiscences of contemporary scientists and includes the photographs showing the development stager.

OPTIMIZATION OF PARAMETERS AND PROCEDURE FOR CALCULATING OF THE SUBMM BAND QUASI-OPTICAL WAVEGUIDE MICROCOMPACT RANGE TESTING GROUND

V. K. Kiseliov

33-41

A procedure is presented for the optimization and calculating of the main geometric and electromagnetic parameters of a microcompact range (MCR). The range is constructed on the basis of the quasi-optical transmission line, i.e. a hollow dielectric beamguide (HDB). The MCR is intended for the laboratory study of the physical object scattering parameters using the quasi-optical waveguide modeling (QWM) method in submm band of electromagnetic waves. Analytical relations are derived and studied, which relate the MCR geometric parameters to the HDB characteristics with regard to the non-ideal waveguide excitation. It is shown that the non-ideal dominant mode excitation at the HDB input makes it necessary to considerably extend the MCR length to retain working volume dimensions at the given allowable level of variations in an incident wave. The conditions are staded to provide for the required purity of the incident field in the working volume and in the MCR receiving zone with the given excitation values a self-filtering coefficient of the HDB dominant mode.

EXCITATION OF THE HIGH-Q-FACTOR WHISPERING GALLERY TYPE MODES IN THE HEMISPHERICAL DIELECTRIC RESONATOR WITH A CYLINDER SHIELD

V. V. Kutuzov, S. N. Kharkovsky, A. E. Kogut

42-45

The hollow metal cylinder with the semicircle at the bases is used as a shield of the hemispherical dielectric resonator with whispering gallery (WG) type modes. It is shown that the spectrum with WG modes of this shielded resonator is far less often than that of the similar resonator shielded with a metal hemisphere. It is found that the high-Q-factor belt modes are excited in the proposed resonator by a coupling slot on the mirror. Their fields are localized in a dielectric. The frequency dependence of the Q-factor magnitude is measured. A good agreement between experimental and theoretical results is obtained.

REJECTION FEATURES OF MULTIPLE RECTANGULAR IRISES

A. A. Kirilenko, L. P. Mos'pan, V. I. Tkachenko

46-52

Rejection features of multiple rectangular irises in a rectangular waveguide are studied be the help of numerical calculations. A qualitative explanation of the mechanism of full reflection resonance formation and the simplest design scheme for the multiple irises with required characteristics are proposed.

SPECTRAL APPROACH TO THE SYNTHESIS OF METAL GRATING ANGULAR AND FREQUENCY FILTERS

S. L. Senkevich

53-59

A non-traditional method of synthesis of metal grating angular and frequency bandpass filters based on the analysis of spectrum of complex eigen frequencies of resonators forming a filter is described. Two types of filters, the resonators of which are formed by two infinite metallic strip periodic gratings in H- or E-plane, are considered. It was shown that filters of the first type has spurious passbands, they are more difficult in manufacturing and the suggested method has an advantage over a traditional approach in high frequency range.

SOME FEATURES OF METER BAND RADIOWAVE SCATTERING NEAR DIFFRACTION HORIZON

V. A. Kortunov, V. N. Gorobets, F. V. Kivva

60-64

Peculiar features of meter band signals near the diffraction horizon are considered. It is shown that in terms of experimental date these features result from the joint influence of radiowave and scattering mechanisms.

ON THE POSSIBILITY OF DETERMINATION OF DIFFRACTION HORIZON USING FIELD HIGH ALTITUDE PROFILE

V. A. Kortunov, V. N. Gorobets, F. V. Kivva

65-67

A possibility of determining of the diffraction horizon using a field high-altitude profile obtained in the area of diffraction and scattering mechanisms is considered. It is shown that this method may be used along with the currently available methods.

ATTENUATION FACTOR FOR Х- AND KA-BAND NEAR SEA SURFACE

V. B. Razskazovsky, Yu. A. Pedenko, Yu. F. Logvinov, V. A. Kirichenko

68-77

The results of the experimental investigations into the attenuation factor of the electromagnetic field in X- and Ka radiowave band for its propagation at grazing angles nearly the sea surface have been analyzed. Attention is devoted basically to the statistical parameters of the field in the space area that corresponds to the penumbra in the standard refraction conditions. The characteristics of the attenuation factor are discussed. They are needed to compute the radar station power potential. Specifically, they are: mean values, distribution laws and the spectra of its fluctuation depending upon a distance and the observation point above the sea surface.

METHODS OF IMPROVING ACCURCY OF LOCALIZING INHOMOGENCITY BOUNDARIES IN SUBSURFACE SENSING

V. G. Sugak

78-82

A possibility has been experimentally shown of improving the accuracy of localizing subsurface of subsurface inhomogeneity boundaries when sensing at depths of 10 m using the signals with a linear FM carrier in a frequency range up to 200 MHz. It was achieved through the compensation of dispersive properties of soils and by using the spectral methods of estimating echo-signals with a high resolution in frequency (in depth). The experiments were conducted on a land plot with specially equipped subsurface layer at a depth of 1 m using the model of a ground penetrating radar. The electrical characteristics of ЕРУ layer differ from one of around medium.

MODIFIED ALPHA-TRIMMED FILTER FOR PROCESSING HOMOGENEOUS REGIONS OF RADAR IMAGES

V. I. Chemerovsky

83-88

The modified alpha-trimmed filter properties are investigated of multiplicative noise suppression and spikes removal from homogeneous regions of radar images. The analysis was performed with regard to the peculiarities of real SAR-images and in comparison to well-known filtering algorithms. Good output results and computational efficiency of proposed version of alpha-trimmed filter allow to use it in the structure of locally-adaptive filters.

MODEL PROBLEM OF SUBSURFACE IMPULSE SENSING AND ITS SOLUTION BY A FDTD-METHOD

N. N. Maita, A. O. Perov

89-93

In the present paper an algorithm for the solution to an one-model problem of subsurface impulse sensing FDTD (Finite-Difference Time-Domain) method has been constructed. An efficient solution to the problem is found by deducing the exact АВС (Absorbing Boundary Conditions) which do not distort physical processes simulated by mathematic tools. The algorithm of the problem solution is implemented in a computer program enabling the data-acquisition process to be visualized and the obtained information to be efficiently analyzed.

OSCILLATIONS OF SEMIBOUNDARY PLASMA AND ELECTRON BEAM PASSING THROUGH INTERFACE

V. M. Yakovenko, I. V. Yakovenko

94-98

In the suggested paper the evolution of the initial state of the semi-boundary plasma and the electron beam passing through the boundary is investigated. Eigen frequencies and oscillation decrements of a system are found. It is shown that under certain initial conditions in the system the increment of coupled surface and volume oscillations is possible.

ON QUASI-STATIC DISTRIBUTION OF EXTERNAL ELECTRIC FIELD IN SEMICONDUCTOR HETEROSTRUCTURES WITH QUANTUM WELL

V. I. Khizhnyi

99-102

For the case of low temperatures the distribution of external quasi-static electric field in heterostructure containing a conducting two-dimensional canal is found as a function of its parameters. The temperature evolution of the field distribution is considered.

QUASI-TWO-DIMENSIONAL MODEL OF CARRIER TRAPPING IN A GAAS MESFET STRUCTURE

N. B. Gorev, Yu. A. Kovalenko, I. F. Kodzespirova and E. F. Prokhorov

103-105

For a GaAs metal-Shottky gate field-effect transistor (MESFET) based on a three-layer system "film-buffer layer-substrate" a simple quasi-two-dimensional model of carriers trapping from the gate static high-field domain in the film to vacant deep centers in the buffer layer and substrate is proposed. Typical calculated results are presented.

QUANTIZING OF GROUP VELOCITY OF SURFACE POLARITONS IN FINITE SUPERLATTICE IN A HIGH MAGNETIC FIELD

J. V. Bludov

106-114

The paper deals with the theoretical investigation of surface polaritons (SP) in the superlattice (SL), consisting of the finite number of infinitely extended two-dimensional electron systems (2DES) arranged at the equal distance from each other. The finite SL was considered to be placed into the constant quantizing magnetic field, directed along the axis of SL. Two cases are under consideration: the case, when the dielectric constants of the media inside the SL () and outside it (₁) are equal and the case, when they are different. It's shown that under the integer quantum Hall effect conditions all characteristics of the SP are represented by the quantized values. It's found that in the vicinity of cyclotron resonance (CR) the SP group velocity with the varying of magnetic field is quantized into steps defined by the fine-structure constant  , the distance between the adjacent 2DES d and the values  and ₁. The influence of the dissipation in 2DES on the SP spectrum and dumping is investigated. The new mode of the SP - an additional SP, which is dissipative by it’s nature and whose properties depend strongly on the momentum relaxation frequency of electrons  is found.

QUASI-OPTICAL SOLID-STATE OSCILLATORS

A. I. Borodkin and B. M. Bulgakov

115-129

The paper is a review of investigations of solid-state millimeter-wave oscillators with a quasi-optical resonance system. Many results have obtained by authors as an originally one and can be used for the design of oscillators with high stability and low frequency noises, and the oscillators with power combining of a great number of low power semiconductor elements in common resonator. Especially is interesting that quasi-optical engineering, which have considered in the paper, has not got any limitation for shortening wavelength and can be it is easy used for the submillimeter wave band. The open resonators with inhomogeneities, which allow placing semiconductor elements and effective they use into resonator, have analyzed in the paper. The different oscillator designs of and its base properties have described. The result of investigation of quasi-optical power combiner has been described.

INVESTIGATION OF THE DIFFRACTIONAL RADIATION GENERATOR WITH LOCAL MAGNETOSTATIC INHOMOGENEITY IN INTERACTION SPACE

A. I. Tsvyk, A. V. Nesterenko, V. N. Zheltov

130-136

Possibilities of improving an efficiency of energy-exchange processes and output characteristics of the unrelativistic diffractional radiation generator (DRG) by creation the local magnetostatic inhomogeneity (LMI) of the field in the interaction space. A theoretical analysis of forming the LMI field by a ferromagnetic rod and of the effect of this inhomogeneity to excitation of electromagnetic oscillations in the DRG has been performed. It is shown experimentally that using the LMI field in the DRG makes it possible to improve the start, power and spectral characteristics of the generator in the frequency range between 40 and 80 GHz. The first specimen of a mm-band packaged DRG having a series of improved output parameters as compared to the well-known devices of this type is reported to been developed.

THE ELECTRON BUNCHES VOLUME INTERACTION WITH THE HF FIELD IN THE RESONATOR WITH A TRANSVERSE WALL

M. V. Mil’cho

137-141

The volume interaction of a modulated electron beam having the volume resonator HF field with the electron beam falling upon the resonator wall, which is placed transversely in the electron flow direction, has been analysed. It is shown that the electron efficiency does not depend upon a transit angle. It has been demonstrated that resonators with very large transit ducts and thick electron beams can be employed. The perspective of the developing of new electro-vacuum devices with the resonator transverse wall has been estimated.

EXCITATION OF THE DIFFRACTION RADIATION GENERATOR WITH DOUBLE PERIODIC STRUCTURE AT DOWNCRITICAL FREQUENCES

M. Yu. Demchenko, V. K. Korneenkov, V. G. Kurin, B. K. Skrynnik

142-145

The functioning of a diffraction radiation generator with a double synchronous grating limited by width in volume and surface waves modes at the frequency below a critical one are studied. It is shown that in periodic structure elementary cell, with the operating and critical frequencies getting closer to another, the H₁₀ original mode is transformed to modes for a separate single grating. The magnetic-field vector H of these modes is directed along the resonator axis. Such oscillations in the elementary cell do not have a critical frequency because the cell structure in the direction of the vector H, i.e. from the side of the mirror is opened.

WIDEBAND PACKAGED BWO OF MILLIMETER BAND WITH 1 W POWER LEVEL

I. A. Vyazmitinov, V. Je. Kapitonov, A. Ja. Kirichenko, I. V. Lopatin, A. S. Tishchenko,

A. Kh. Khudaiberganov

146-149

A compact wide band BWO of 8mm-range has been developed and investigated. The band of continuous electric frequency change of the BWO exceeds 10 GHz at accelerating voltages below 2000 V and a rate of change» 8 MHz/V; weight is 2.5 kg, service life is over 1000 hours. In the frequency band of 33 to 37 GHz the output power reaches 1.2 to 1.3 W at power drops of no more than 2 dB, electron efficiency is up to 3% and accelerating voltages are 1400 to 1800 V. The development of a BWO with these parameters results from a complex approach to its design and a choice of separate elements, as well as from using an efficient electron-optical system.

RESONATOR SYSTEM FOR LOW AND SUPERLOW VOLTAGE MAGNETRONS

G. Ya. Levin, S. N. Terekhin, M. O. Khorunzhiy

150-152

A comparative analysis of resonator systems comprising a resonator of “sector”, “sector-sector” and “slit-sector” type has been made. It is shown that systems having a more complicated configuration make it possible to decrease the anode voltage and improve resistance to thermal loads.

TUNABLE PULSE-PERIODIC DYE LASER

M. I. Dzyubenko, V. V. Maslov, V. P. Pelipenko, V. V. Shevchenko

153-157

The spectral-power characteristics of high-power tunable flashlamp-pumped dye lasers operating in a pulse-periodic mode are investigated. It is shown that appropriate mixtures of effective donor-and-acceptor dyes can be utilized to ensure a smooth variation in a working range of these lasers.

MODELING OF QUANTUM WELL LASER DYNAMIC BEHAVIOR WITH REGARD TO CHARGE CARRIER TRANSPORT EFFECTS IN A ARGE SIGNAL MODE

I. A. Sukhoivanov

158-165

The existing models for representing the dynamic behavior of high-speed quantum well semiconductor lasers do not after a full picture of the physical processes occurring in these devices. Based on the study of the charge carrier transport a new physical model is proposed and a dynamic model for the numerical investigation into the high-speed quantum well lasers is formulated.