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The finite element method for simulation eigenmodes of the gyrotron cavity is presented. Weak form of the boundary value problem based on the penalty function method is obtained. For the numerical simulations, Comsol Multiphysics software package is used. Field profiles, cold frequencies, and Q-factors for several cavity eigenmodes are calculated. The results are compared with the cross-sections method,...
Ten microstrip bandpass filters with wide high-frequency stop band are investigated with the help of the numerical electrodynamic analysis of 3D models. From each resonator bandwidth of the offered filters tuned with a relative width ∆f/f0=20% is formed by one lowest oscillations mode only. However at all microwave devices the extended high-frequency stop band is observed due to large leap of lines...
It is shown that in the area of three-dimensional interaction radiation communication system of oscillators leads to a build-up phase group and the total dipole moment in time. Within the framework of a simplified three-dimensional problem studied self-excitation of the small portion of the active medium. In addition to the cross motion of electrons in each ensemble accounted longitudinal movement...
This paper presents the results of numerical simulation and experimental researches of high power broadband TWT in X/Ku frequency range. Described TWT provides the output power more than 500 W with the operating frequency greater than 1 octave and gain coefficient more than 30 dB. In this TWT is used periodic magnetic focusing system for maintaining the electron beam. TWT has a waveguide output and...
The distribution of energy deposition in the dielectric layer, moving by circular paths within the electrodynamic system constructed of the plurality of parallel groove waveguides (GW) is investigated. The main simplified engineering models for calculating the microwave electromagnetic field distribution and energy losses in such systems are created. The calculations fulfilled for the case of dielectric...
A short overview of measuring methods for dielectric constant in SHF range is given. A 3-D numerical simulation of microstrip structure with a central electrode of an interdigital type loaded onto a thick-film material sample was carried out. Resonance frequencies of wavelengths in cm-range depending on dielectric constant of the measured sample were determined. A correlation between resonance frequency...
The current status of the various theoretical approaches to the description of turbulence in the electron flow and electronic devices of ultrahigh frequencies (UHF) is shown. A three types of turbulence in nonlaminar electron flow were considered. The first type of turbulence is caused by the intersection of the electron trajectories (eg, due to thermal velocities) and it is common to all the electron...
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 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...
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...
This paper presents an optimization of the waveguide-supplied coaxial-line-based nozzleless microwave plasma source. This field applicator operated at a frequency f equal to 915 MHz at an atmospheric pressure. The optimization objective was to maximize an efficiency of power transfer from electric field to plasma inside this device. In the optimization we used a model of plasma which was determined...
A 8-mm extended interaction klystron with a sheet electron beam and a modulator was developed. The klystron operates at cathode voltage 10 kV and cathode current 2,6 A. Mathematical simulation methods and computer codes MEMFIS (electrodynamics system), CST Particle Studio (electron gun, interaction processes, collector) and Ansys Maxwell (magnetic focusing system) were used in the development process...
Possible ways for designing super-high power pulsed klystrons at significantly decreased operating voltages have been considered. They include the following: — the development of principles for designing klystrons with magnetron gun with anode modulation, positioning several such klystrons in a single solenoid with homogeneous magnetic field and summation of their output powers. — the development...
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 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...
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