2002, volume 7, № 2

EXPERIMENTAL DETERMINATION OF EQUIVALENT CIRCUIT PARAMETERS OF OPEN RESONATOR COUPLED TO TRANSMISSION LINES

Miroshnichenko V. S., Senkevich Ye. B.

301-311

The method of determination of equivalent circuit parameters for open resonator having radiation loss in coupling port has been considered. As a basis of the method the linear fractional curve-fitting procedure for complex reflection coefficient data measurements in n ³ 3 points near the resonance frequency has been used. The experimental test of the method has been performed in 8-mm waveband for several types of coupling ports. The radiation losses behavior of coupling ports near the resonance frequency have been investigated; the excitation efficiency and the energy output efficiency of open resonator have been determined.

SELF-SHADOWING INFLUENCE ON THE REFLECTION FROM A RANDOM STAIRCASE SURFACE

Pazynin V. L.

312-316

The beam reflection from a staircase surface with a stochastic stair size is considered the using geometrical optics approach. The self-shadowing coefficient of such surface is constructed by means of two auxiliary functions, each being the solution of an integro-differential equation. In this paper, the exact solution of these equations is constructed for the exponential function of the stair height distribution density. In contrast to the earlier investigations, this solution is validated for the finite distances between a transmitter and receiver and a random surface.

STATIC ELECTRIC FIELDS IN REVERSE-BIASED PN-I-PN STRUCTURES

Lukin K. A., Maksymov P. P.

317-322

Static electric fields in GaAs, Si and Ge reverse-biased pn-i-pn structures are investigated. Analytical formulas for the electric field and electric potential in homogeneous doped pn-i-pn structures have been obtained. Both geometry and doping profile of these structures are evaluated. The conditions of existence of a positive feedback via drift current between two  junctions are determined. It is shown, that varying parameters of the reverse-biased pn-i-pn structures one can provide the required distribution of the static electric field in the areas of the structure and necessary multiplication rate of the electron-hole of pairs generation in the p-n junctions.

А RESONATOR FOR SELECTION AND FORMATION OF A FOURIER MODE WITH A UNIFORM PROFILE OF A FIELD AMPLITUDE

Gurin O. V., Maslov V. A., Svich V. A., Topkov A. N., Fursova E. V.

323-327

By using a spatial Fourier-filtration, the description is given of the method of selecting and forming, in a generalized confocal resonator, the Fourier mode with the field amplitude distribution, close to uniform, on one of the mirrors. Based on the numerical calculations of the characteristics of the even-symmetric lowest-modes, both the resonator and its amplitude-step-like mirror geometry for the formation of such beams have been found.

NEW METHOD OF DIELECTRIC PERMITTIVITY MEASUREMENT OF INHOMOGENEOUS DIELECTRIC STUFFS

Budanov V. E., Yevich N. L., Suslov N. N.

328-334

The new method of measurement of value of average dielectric permittivity of inhomogeneous dielectric stuffs relating to the class of polymer aggregates which works in the millimeter wave-band of electromagnetic waves is offered. For practical implementation of the method the two-shoulder antenna with piecewise linear phase distribution of fields was designed. During measurements the phase difference of the fields at the joint of shoulders varies proportionally to their length.

MILLIMETER WAVE SCATTERING BY VEGETATION COVER

Roenko A. N., Zamaraev B. D., Kostina V. L., Timoshenko V. F.

335-341

The results of “water cloud” model application for electromagnetic energy scattering by the surface covered with vegetation are considered. Vegetation is presented by grass. One of the possible ways to solve inverse problem, i.e. to define cover mass-weight indexes according to measured  value, is shown.

ENERGY LOSSES OF A CHARGED PARTICLE DUE TO EXITATION OF HELICONS IN A SOLID-STATE PLASMA

Khankina S. I., Yakovenko V. M., Yakovenko I. V.

342-346

The particle’s energy losses due to Vavilov-Cherenkov radiation of helicons have been studied. The particle is running along the spiral line relative to the constant magnetic field direction. It is found that the losses mentioned are equivalent to those of  the energy of the magnetic moment produced by rotation of a charge. Here, the magnetic moment is moving at a constant velocity along the magnetic field. It is shown that the Vavilov-Cherenkov radiation of the magnetic moment forms the basis of the collisionless damping of helicons.

NONLINEAR SURFACE POLARITONS IN A TWO-DIMENSIONAL ELECTRON SYSTEM PLACED INTO THE EXTERNAL QUANTIZING MAGNETIC FIELD

Beletskii N. N., Bludov Y. V.

347-357

The paper deals with the theoretical investigation of nonlinear surface polaritons (NSP) in isolated two-dimensional electron system (2DES) arranged at the interface between two nonlinear media and placed into the external quantizing magnetic field directed perpendicularly to 2DES. We assumed that nonlinear medium dielectric permittivity is the quadratic function of the tangential component of electric field. It is shown that under integer quantum Hall effect conditions all NSP characteristics are represented by the quantized values. It is found that NSP can exist only in the case when the value of a tangential component of electric field at the interface is less than some critical value. It is found that in the case when 2DES lies at the interface NSP spectrum contains four modes. Two of them possess the normal dispersion and two other possess anomalous dispersion. It is shown that NSP modes which possess anomalous dispersion exist at small values of wavevector only. It is found that in the case of symmetric surrounding of 2DES the NSP spectrum contains only two modes.

PECULIARITIES OF NONLINEAR STABILIZATION OF PLASMA-BEAM INSTABILITY IN SEMICONDUCTOR GAAS

Averkov Yu. O., Yakovenko V. M.

358-364

The excitation of nonlinear plasma oscillations by a monoenergetic electron beam of low density moving through a semiconductor is considered by the particle-in-cell method. An electron beam is assumed to be a sequence of electron bundles with constant density. The case is studied when the electron collisions frequency in a semiconductor is greater than the hydrodynamic increment of instability in collisionless plasma but less than plasma electron frequency. The influence of nonparabolicity of electron dispersion law and intervalley electron transitions on the plasma-beam instability is taken into account. The nonparabolicity is shown to lead to the decrease of the maximum of the electric field amplitude while the intervalley electron transitions bring into existence a plateau on the temporal dependence of the slow amplitude of the electric field.

TRANSFORMATION OF INFORMATIONS AT ACOUSTOOPTICAL INTERACTION

Danilov V. V.

365-372

The results of investigation of a process of transformation of RF signals in their acoustic and further in light clones in the form of a diffracted laser bundle without distortions at acoustooptical interaction are presented.

HIGH-EFFICIENCY MICROWAVE BJT POWER AMPLIFIER ANALYSIS

Rudiakova A. N., Rassokhina Ju. V., Krizhanovsky V. G.

373-378

The paper presents the analysis of the high-efficiency power amplifier using driving signal power in order to increase efficiency. The described approach is effective especially for devices operating with a low power gain, in which driving power is the same order as an output. The KT911 BJT power amplifier simulation was performed. As high PAE as 87.5% was achieved. The collector current was negative during the considerable part of ac period, along with always-positive collector-emitter voltage, thus the instantaneous dissipated power also became negative, that lead to the efficiency increasing.

10 THZ LASER SOURCE OF RADIATION

Kamenev Yu. E., Kiselyov V. K., Filimonova A. A.

379-380

A laser source of continuous radiation with the output power of ~2 mW has been described. Water vapors excited by the high-frequency discharge (13.5 MHz) are the working substance. The length of an active zone is 1 m, the internal diameter of a discharging tube is 32 mm.

COMBINED PUMPING OF A COMPACT HCN‑LASER WITH THE DUPLEX LASER  EMISSION OUTPUT

Kamenev Yu. E.

381-384

An HCN-laser with the length of the active zone of 0.5 m has been described. The polarization-and-energy characteristics have been studied which depend on the electromagnetic parameters of outlet mirrors made in the form of two crossed one-dimensional wire gratings.

RESEARCH OF THE PULSE-PERIODIC SOURCE OF RADIATION THAT CAN BE TUNED WITHIN ULTRAVIOLET-RANGE OF SPECTRUM

Dzyubenko M. I., Kolpakov S. N., Pelipenko V. P., Shevchenko V. V.

385-391

There was investigated the influence of parameters of tunable radiation of flashlamp-pumped dye-lasers on the second harmonic generation in different ranges of spectrum. It is established that the requirements to divergence of radiation of the dye laser grow at increase of spectral width of line. There was developed the pulse-periodic source that can be tuned within UV-range of spectrum (260-340 nm); its the average power is equal to round a few tens of mW, and peak power is equal to a few units of kW.

TUNNEL CATHODE FOR GUNN DIODE

Botsula O. V., Prohorov E. D.

392-396

The n⁺-D-n⁺ Gunn diode with dielectric on the basis of wide – zone Al_0,2Ga_0,8As. semiconductors have being considered. The model is permit to analyse the oscillation mode of the diode is proposed. The peculiarity of electron transfer and current instabilities are analysed. The energy characteristics the structure working in sm-wave range are received. The perspectives of using of considered structures are showed.

ELECTROSTATIC POTENTIAL DISTRIBUTION IN ECCENTRIC CHANNEL WITH TUBULAR ELECTRON BEAM

Alexeev G. A., Stulova L. V.

397-400

The analysis of a static potential distribution in a cross-section of the equipotential cylindrical channel with the tubular electron beam is performed at both symmetric and eccentric dispositions of the electrodes. It is shown that a smooth change of the channel width does not allow to form an effective (“narrow” and “deep”) natural ion trap in the azimuth direction with small loss of the beam current.

TESTING OF A SOFTWARE PACKAGE OF POISSON’S EQUATION SOLUTION FOR MATHEMATICAL MODEL OF A MILLIMETER MAGNETRON

Volovenko M. V., Nikitenko O. M.

401-405

An accuracy of Poisson’s equation solution by numerical method for crossed field systems is considered in the given paper. A comparison is made between the numerical and analytical results of Poisson’s equation solution for some classes of the spatial charge distribution function. Comparative characteristics of Poisson’s equation solution by the numerical and analytical methods are given.

CORRELATION-SPECTRAL PROPERTIES OF CHAOS IN THE NONLINEAR DYNAMICAL SYSTEM WITH DELAYED FEEDBACK AND ASYMMETRIC NONLINEAR MAP

Zemlyaniy O. V., Lukin K. A.

406-414

In this paper the nonlinear dynamical system with delayed feedback is investigated by means of numerical methods. The nonlinearity is presented by asymmetric 1-D map. The relation between correlation-spectral characteristics of chaos and nonlinear map properties was found. The obtained results can be used for development of RF-band chaos generators with prescribed statistical properties of output signal.

APPLICATION OF THE METHOD OF THE POLYNOMIAL MAXIMIZATION FOR ESTIMATION OF SIGNALS PАRАMETERS RECEIVED BY THE ANTENNA ARRAYS

Y. P. Kunchenko, T. V. Prokopenko

415-418

In this work the method of the polynomial maximization of a case of finding of estimations of signals parameters justified at observation of a vectorial random variable. The algorithms of finding of estimations of scalar and vectorial parameters of a vectorial random variable, and of property precision of received estimations are resulted in the work.

THE INDICATOR OF OSCILLATION FREQUENCY FOR A POWERFUL IMPULSE AUTO GENERATOR

V. I. Beloglazov, А. N. Dovbnya, P. I. Mos’pan

419-421

The paper presents the device description which destined for control of oscillation frequency that is generated by powerful impulsive klystron auto generator, going in composition of linear electrons accelerator. In the device a transformation principle of explored frequency with consequent modulation is used. The frequency indicator enables one to control significance of explored generator frequency f_ent » 2797 MGz with » ±25 kGz accuracy, going in routines continuous and impulsive, as during lasting exploitation, so and inside of every impulse. Experience of quinquennial exploitation bore out that such a device is unchanged one for linear electron accelerator exploitation.

THE PHOTOMETRY OF EMISSION OPTICAL SPECTRUM BY LINE IMAGE SENSORS

Yegorov A. D., Yegorov V. A., Yegorov S. A., Zdor E. V.

422-425

The present paper deals with the issues relating to the correctness of using the rectangular gem of smoothing in the determination of the analytical parameters of spectral lines on the emission spectrometers having multi-cell photodetectors. The techniques for the photometry of optical spectra recorded through the use of photographic carriers and multi-cell photodetectors are shown to offer some essential differences. Use of the rectangular gem of smoothing with an indefinite phase and half-width of a spectral line may lead both to the loss of photometry accuracy and deterioration of resolution. The dependence of the value of the component of an error in determining the amplitude magnitude of the light flux of the spectral line maximum upon its half-width and the position with respect photodetector pixels is considered. The method of the correct solution to the problem is discussed.