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As a result of the numerical 3-D simulation it was determined the optimal process parameters of multi-mode interaction with a multi-beam electron flow for a new type of klystron spatially-developed double-gap quasi-fractal cavities (DFRC). Such cavities can be tuned at fundamental and doubled operating frequencies which are corresponding antiphase and inphase modes simultaneously. It is showed, that...
The natural frequencies of the multimode microstrip resonator «hairpin with stub» were investigated from its constructive data. Application in the resonator of the stub allows not only to observe on amplitude-frequency characteristic the poles of power attenuation, and also to considerably reduce frequencies of all its even modes of oscillations. At the same time frequencies of odd modes don't change...
The method of digital calculation of noise figure for helix TWT using 2d code are presented. The electron beam in helix structure enter was obtained after electron gun calculation with current and velocity modulations on cathode. The zero initial conditions for electron beam in helix enter for interaction calculation was changed by conditions which taken into account current and velocity modulations...
The investigation of sensitive element on the planar mushroom-shaped metamaterial are considered. The results of numerical simulation sensitive element for measurement of physical quantities and monitoring parameters of technological processes using CST Studio Suite are presented. Also it is shown that the microstrip sensitive element has geometrical dimensions much smaller operating wavelength while...
The application field of radio electronic devices is expanding, and with each year these devices become more complex. It is also true for devices, working within the SHF range. Due to the broadening of options of the radio electronic equipment, some devices become quite massive, and so a need to miniaturize them arises. This paper contains the analysis of miniaturization based on the microstrip filters...
This article is devoted to the research on a way to miniaturize a microstrip branch-line hybrid coupler. The construction miniaturizing is based on a simple bend of a micro strip line. This way is simple as it does not require complex mathematical calculations. During the process of design it was taken into account that compact devices should have similar characteristics to those of conventional constructions...
A mathematical model of broadband TWT, which allows for the mathematical modeling of nonlinear amplification of broadband dual-frequency signal with equal amplitude on the basis of information about the family of its single-frequency characteristics in the operating frequency band. This signal is widely used in practice for the assessment of non-linear properties of TWT. It is proposed for modeling...
This work presents the application of harmonic balance method to the analysis of steady state mode class E amplifier using power tube. The mathematical model obtained by the harmonic balance method allows taking into account the finitude of RF choke and blocking capacitor values, as well as active element anode voltage drop in conducting state. The model does not use iterative methods of active element...
This report tells about the behavior of charged particles in the crossed fields with parametric generation of high-frequency oscillations in the initial period of time. Authors consider the radial resonator system, with two coaxial cylinders and inhomogeneous magnetic induction, and determine electron trajectories in crossed fields. Trajectories were determined in case of ac magnetic and electric...
This paper presents research results of field-emission processes in cells containing the cathode in the form of matrix points made of glass carbon and cell separated by the film of borom nitride. It is experimentally registered decreasing of surface insulating properties of the dielectric film inside of the cell in reaching the cathode current density 0,2 ÷ 0,3 A/см2, bringing to appearance of increasing...
The report examines the most common microwave vacuum electronic devices (triode, tetrode, diacrode, klystrons, IOT, magnetron, gyrotron, BWO). It noted the main features of their work. The limiting parameters and characteristics of these electronic devices made to data. The estimation of the prospects of the use of ISM-technologies in the short-range microwave. It is noted that in addition to the...
The method of space charge forces calculation in nonstationary electron beams using boundary elements equations are proposed. For 1D task the consistent scheme of distribution between mesh points of particle charges and calculation of electric field acting on particle is considered. This scheme eliminates effect «self-action» of particles but decreases the accuracy of force acting between two particles...
The paper discusses the possibility of forming electron beam in a field emission cells with high (∼ 1000) ratio of the tips' height of the glassy carbon to their radius of curvature. The possibility of creating such a field emission cell, protected by ions, without beam loss on the grid and on the anode is shown. A comparison of the characteristics between considered cells and Grigoriev-Shesterkin...
The paper examines the way of separating a regular component in the electrical signal based on the analysis of the representative point trajectories in the phase plane. The work presents an algorithm for constructing the phase diagram of the process according to signals received from piezoelectric transducers. Mathematical support for calculation of the regular component based on the density analysis...
It is suggested the concept of a switching function used for the linearization of the static converter circuit in the analysis of steady-state and transient, defuse to the formal decision of problems of synthesis. The article shows the possibility of presenting switching functions in the basis of binary operations of choice of implicative algebra for the identification of individual variables with...
For complex plants the composition of the intellectual control systems and neurocontrol is offered. The developed approach is based on: 1) synthesis of the stabilizing control law on the aprioristic information; 2) plant's parametrical identification on experimental data; 3) synthesis of the «exact» control law on the basis of the specified plants model; 4) realization of the «exact» control law an...
Article associated with a type of gasothermic processing, namely the detonation-gas treatment, which today is less popular due to the physical characteristics of the process. Material is overview and summarizes the results of the work in the field of gasothermic. The article discusses the mechanism of combustion of hydrogen-oxygen mixture as the main working gas in detonation-gas spraying coatings...
The basic principles to be met by structural and functional diagram of the device of detecting of high-voltage overhead power lines with low-altitude helicopter flight. High-voltage lines are a common cause of helicopter accidents. A possible structural and functional diagram of the device, as well as the formula to calculate the required sensitivity of the sensors of electric and magnetic fields...
A use automatic network analyzer based on down conversion of measuring frequency of multi-port reflectometer ports' responses is proposed to overcome the problem of weak tag signal blocking by a high-power carrier signal from reader. This approach does not require the carrier signal reader compensation. The basic measuring equations of the new meter are obtained. The advantages of the proposed meter...
The article deals with the possibility of using microwave energy to heat concrete before pouring into molds. The experimental researches of increase of heavy concrete strength at microwave heating are made. The perspectives of the rapid microwave concrete hardening at 40–60 °C are shown. The possibilities of creating of high-power microwave installations for preheating of concrete mixtures using waveguide...
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