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The present paper is focused on the possibility of designing small-size pulsed cold-cathode SWMs for THz frequencies us ing 3D numerical simulation. Such sources with an output power varying between hundreds of mW and units of kW may be employed, for example, in the development of high-resolution radars, as well as in the desktop charged-particle accelerator technology, in communication links between...
The aim of the present paper is to address the issues whether it is possible to design and develop by numerical simulation the electromagnetic continuous-wave THz-sources width electrically tunable frequency. These sources may well find their use, in the fields of applications such as the development of THz spectroscopy, high-resolution radars, and communication lines between super, high-speed computers...
Radiation pattern and electromagnetic field interaction power have been analyzed depending on the electron beam proper field in diffraction radiation mode. This paper discusses two cases: in the linear case interaction power is increased by electron beam and in the case of synchronism with fast space charged waves, interaction power falls, so that the field amplitude increases, the electron beam is...
In this work the linear self-consistent theory of amplifier is developed on Smith-Parcell effect at co-operating of ES with the fields of periodic metallic structure. Dispersion equalization allowing probing electronic-wave processes, flowing in the opened waveguide at the eventual value of the focusing magnetic field is obtained
Basic properties of "classical" open resonators (OR) without discontinuities are briefly stated. Properties of OR with periodic metal discontinuities, coupled OR, and also different modifications of the resonance open metal-dielectric structures are considered
Basic properties of the open resonators (OR) without discontinuities are investigated as base systems. Influencing of dielectric discontinuity is specified as dielectric prisms (DP), and metallic discontinuity, being band diffraction grating (DG), on spectral and resonance property of base OR
Generators for a millimeter and sub-millimeter wavelengths range with the use of klystrons principle of interaction are presented. It is shown, that the calculated electron efficiency of orbotron-klystrons on frequencies 50-300 GHz reaches up to 16-54%. Output power of klystron-frequency multipliers reaches 2.6-39 W on frequencies of 500-2000 GHz
With the help of computer modelling the irregularity influence of a comb upon properties of two-cascade orbotrons-amplifiers, and also frequency multipliers of electromagnetic fluctuations of a millimeter range is investigated
The research of multidimensional model of two-stage frequency multiplier with multibeam election-optical system is carried out. The presence of multiple-speed electronic stream allows effectively controlling the characteristics of interaction between high-frequency field and charged particles. On the basis of beam-wave interaction multidimensional nonlinear theory, increase conditions of output power...
A possibility has been experimentally shown for increasing output power and extending the generation frequency bandwidth of the DRO when the diffraction grating is like a non-uniform chain of coupled millimeter-wave (70-92 GHz) half-wavelength resonators (CCR)
A possibility of frequency modulation of terahertz gas-discharge laser within the limits of the width of active substance spectral line when modulating the pumping current has been considered. At the same time it is possible to compensate parasitic amplitude modulation partially if operating range of current change is chosen properly
The 3-D model of the secondary-electron multiplication dynamics in cold cathode magnetrons having a SEC (second emission cathode), which is bombarded by the primary electrons from the side thermionic emitter. The carried out calculations of start magnetron processes with various values of a injection current shown, that generation in magnetron comes at any injection current, however start time of...
The obtained outcomes of mathematical modeling and experimental investigation allow better to understand physics of the processes of tuning frequency and phase lock in magnetrons and will be useful for the designers to create of the coherent magnetrons with the improved frequency characteristics
Presented in this paper are the results of experimental research of klystron active oscillators synchronization. It was found out that depending on the nature of the connection and operating modes, mutual synchronization, synchronization with chaos suppression, full synchronization of these active oscillators may be observed
Presented in this paper are the results of unsoldered electron gun design for transmitting broad ribbon electron beam into the atmosphere or other gas medium. The gun uses ribbon cathode 320times6 mm2 , rectangular focusing electrode located near the cathode with slot holes on the edges of its wide side walls and anode as a hollow tube with rectangular cross-section, whose end is closed with a massive...
Periodical structures are particularly interesting in the optical and near-optical frequency range and may be used to manufacture electronic circuits, devices and unusual optical equipment. In some plates, waves at low incidence angles do not penetrate artificial media, while with increasing incidence angles waves begin to penetrate such media. At the same time, refraction angles decrease at first...
The theoretical analysis results of two modifications of axial-symmetric electron-optical systems with converging optics based upon previously developed algorithm are presented. The information on a structure and distribution of current density of an electronic bunch taking into account settling on electrodes is obtained
Proposed in this paper is dynamic model of thermionic cathode emitting surface. This model fragment makes it possible to simulate the shot component of noise for the base diode cell of electrovacuum device in any mode. Experimental check was executed for the model designed using the samples of oxide cathodes
Considered in this paper is telecommunication system UMDS MITRIS, providing high-tech decision for wide-band distribution networks. It should be noted that UMDS MITRIS is consumer system, which takes into account perspectives of national information systems integrated into European and worldwide infrastructures. It is shown that system architecture provides its compatibility with broadcasting satellite...
Described in this paper are modern services of VSAT-networks, new abilities for telecommunication TV- programs broadcasting with developing of the new standard DVB-S2 and compression standard LtMPEG-4Gt, and the new solution IPTV (MPEG-4 over IP over DVB-S2). The advantages and disadvantages of the new technology MPLS-the technology of the backbone for both terrestrial and satellite communication...
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