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This report considers investigation of parametric generation of high frequency oscillations in radial resonator system with crossed electric and magnetic fields. Usually an investigation in that system was conduct in case of parametric resonance or in case of frequency's double multiplications of ac fields. In this report, the authors show the fundamental possibility of parametric generation in crossed...
The paper describes the basic design and technological features of vacuum photosensitive devices. Investigation of the possibility of intensification of the photoemission process using planar nanostructures with controlled localization of the electrostatic field, which are based on the film of diamond-like carbon, is carried out. It is proposed a phenomenological model that describes the tunneling...
This paper reports the general view of continuous high-power TWTs manufactured in Stock Company «Reseach-and-Production Enterprise «Alm«z», designed in recent years. Also general parameters of high-power broadband helix TWTs in the range from 1 to 18GHz are presented. The width of the most TWT's frequency range — octave or more. TWTs has the output power from 500 to 1500 W. For some TWTs is described...
Equivalent systems method was implemented for designing the resonator slow-wave structures in plasma-beam devices, and non-impact plasma was used for the filling of the transit channel. The collation of the calculation results demonstrates the adequacy of the developed model in comparison with the real devices and structures. The analysis of the slow-wave structure dispersion characteristics was carried...
The paper is aimed at development of miniaturized THz O-type devices with sheet electron beam. A 0,2 THz traveling-wave tube amplifier with a staggered double-grating slow-wave structure (SWS) is designed. The results of calculation of small-signal and large-signal gain are presented. The calculations predict 15–20 dB small-signal gain and up to 100 W saturation power in the amplifier with 20 kV 0,1...
The field emission structure with thin conductive substrate of sufficient width and length with a double-sided emitting surface are tangent to the axis and coated with a nanoscale film of diamond-graphite clusters with pulling electrons grid is considered. The grid potential of the order of several (or tens) of volts generates a potential barrier. The electrons are emitted with approximately the Fermi...
A method of synthesis is developed, equations are derived and results are obtained via this method for simulation of magnetically shielded electron-optical systems that form sheet electron beams with compression. Relation that allow determination of the parameter of the electron guns and deformation of cross-section sheet electron beams in the magnetic field are presented Electron-optical systems...
The application of the voltage converter for the broadband microwave voltage controlled oscillator (VCO) is considered in this paper. Special attention is paid to additional phase noises of VCO by called use of the diode voltage converter. Studies showed, that at analysis frequencies more than 10 kHz additional phase noise spectral density can be reduced due to decrease of the converter load resistor...
The structure of periodic ferrite with thin's modulation which load on periodic ferroelectric studied. The dispersion characteristics was calculated using the modification of finite element method. It is shown, that when ferroelectric load superimposed on the thickest part of the ferrite then changes of permittivity of ferroelectric load influence to band's gap width. It explains the reasons for the...
The ability to achieve the limit values of the klystron efficiency based on COM-bunching mode being considered. It is shown that the most important parameter affecting the transition to this regime is the lumped bunching length (LBL). The dependence of optimal LBL value on the number of cavities was obtained by the step-by-step optimization of different klystrons. It was shown that such a dependences...
Mutual phase locking of gyrotrons is important for power combining applications, especially for electron-cyclotron-resonance plasma heating. In this paper, a model of two coupled gyrotron oscillators is developed and basic properties of the phase locking are studied. Time delay of the coupling signal traveling between two gyrotrons strongly affects the pattern of phase-locking regimes. The model is...
The article considers the possibility of using the ridged waveguide as a measuring cell of devices for determining permittivity of materials. The calculations of electromagnetic fields of hybrid waves were performed for the ridged waveguide with the piecewise-layered dielectric filling by the method of partial regions in view of the behavior features of electromagnetic fields on the dielectric and...
The article deals with the use of a technique of a modified method of the planned experiment to modeling of physical processes in the klystron and electrodynamic systems, developed by the operational method of calculating the klystron cavities, based on the use of approximate models obtained on the basis of equations with refinement coefficients, found by the planned experiment. Application of the...
A novel design of waveguide diplexer for millimeter wave applications is proposed. The diplexer is based on E-plane metal insert filters with ridged sections and longitudinal diaphragms in rectangular waveguide. The diplexer includes the E-plane waveguide bifurcation with parallel waveguide channels and stepped waveguide transition. The proposed diplexer design provides extended stop-band of the filters,...
The principles of creation of huge cathode-heating units with emitting surface a few hundred square centimeters are described. Proposed to use injector with thermionic cathode for forming the electron beam with current 500 to 1000 A and energy 500 keV. Emitting surface of this cathode should be a truncated cone form with a large diameter of 400 mm, slant height 30 mm, apex angle of 120 degrees and...
Analytical expressions for the longitudinal and radial components of the magnetic induction in the reverse magnetic system cell with two ring inserts in case of inner diameter of ring inserts greater than the diameter of the drift tube have been found with the magnetostatic potential approximation. The electron optics calculations of the klystron with magnetic focusing system containing high harmonic...
The paper represents a new concept of thermal infrared sensor array based on the micro(nano)-electromechanical system (MNEMS) with non-stationary Seebeck effect. The application of Seebeck effect readout method in the sensing element using the “switchable” thermocouple is analyzed. The main characteristics of such a sensitive element for an IR imager array and their interrelation are discussed, i...
The practical part of the work on the modernization of the industrial plant of high-frequency sputtering. The author's task was put to create a universal test bench with the possibility of a wide variation of sprayed materials. The versatility of the installation is the possibility of growing films of metals and dielectrics using the same sputtering target. The design of the experimental setup provides...
The paper presents the ways of improving output voltage spectrum in switched-mode generators. Because of errors arising while setting the transistors' switching times, it is rather difficult to achieve the required compensation of higher harmonics. Switching times errors are caused by the inertia of the switching process in power transistors as well as sampling errors of control devices. Analysis...
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