Datasets & Competitions
The concept of “radio travelers” is not familiar to many. These people have all the qualities of travelers: the desire to visit interesting, sometimes hard-to-reach places with an unusual landscape, nature, mountains, sea. Secondly, and this is the main thing: having reached the goal, they continue traveling, but already on the radio amateur air! To do this, participants install antennas, connect amateur radio HF and VHF equipment to them and conduct two-way radio communications. There are quite a lot of people willing to conduct communications with such radio stations.
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4 Views
In order to reduce the dimensionality (reduce the number of features of the object of study), the article uses the methodology of “compendium–table–infographics”. Three projects related to the study of radio wave propagation in the Crimea and the Black Sea Fleet (1914, 1928 and 1954–1955), as well as studies of the physical parameters of fields and environments (hydroacoustic and magnetic fields, radar, thermal and laser characteristics of surface ships, seismic and seismoacoustic waves) are considered.
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3 Views
Sodium tube triode detectors designed by the American radio engineer Harold Donle are considered. An analysis of the operating principle of the sodium detector has been made. Donle's patent for the design of a sodium detector is presented. The first design of a sodium detector lamp, in which a container of liquid metal sodium was used as the anode, is presented in detail. The reasons for refusing further use of this detector lamp design are indicated. Attention is paid to the second improved version of the Sodion S-13 lamp detector using a small drop of sodium the size of a match head.
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5 Views
The paper proposes an analytical model for calculating the normalized equivalent isotropic radiated power, which allows analyzing the applicability of the asymptotic approximation proposed in the 3GPP TR 38.884 report as an acceptable method for reducing the measuring distance when determining the equivalent isotropic radiated power of 5G and higher communication system equipment in the FR2 frequency range.
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7 Views
The paper substantiates the method of orthogonalization of linearly independent functions based on the calculation of the orthogonality weight. The form of orthogonal functions does not differ from the form of the original functions. Synthesis of optimal receivers is carried out based on the criterion of minimum noise variance at the receiver output for a fixed reference value of the useful signal. In the case of non-white noise, op-timal receivers have a finite gain in the entire operating frequency band.
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3 Views
We propose a radar method for determining the roll angle of an aircraft using a passive beacon in the form of a radar polarization-anisotropic trihedral trihedral corner reflector (СR) with a triangular shape of reflecting edges and with horizontal intrinsic polarization. To determine the roll angle, the onboard radar uses probing pulsed radio signals with a linear plane of polarization coinciding with the transverse axis of the aircraft. Reception of reflected pulse radio signals from the passive beacon is carried out on board the aircraft in a circular polarization basis.
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5 Views
The article analyzes the methods for measuring the radio frequency parameters of 5G subscriber equipment in the millimeter wave range for the scenario of autonomous deployment (SA) of the 5G RAN radio access network and shows the features of these measurements associated with the need to carry out them using Over-the-Air methods. The issues of analyzing the parameters being tested, analyzing the methods of Over-the-Air measurements for testing 5G subscriber equipment and improving contactless testing methods are considered.
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3 Views
Success in creating the BINP SB RAS S-band klystron with an output power of 60 MW set the team a new task of creating a C-band klystron, since the global practice of developing modern charged particle accelerators tends to move towards higher frequen-cies. The designed C-band klystron has a twice higher operating frequency of 5712 MHz.
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4 Views
The article presents the results of a comprehensive theoretical and experimental study of ferromagnetic resonance and microwave magnetoelectric effect in multilayer ferrite-piezoelectric structures containing single-crystal iron-yttrium garnet of cut (111) in combination with piezoelectric materials. Mathematical modeling of physical processes occurring in ferrite was performed, which made it possible to reveal weak magnetic cubic anisotropy, which must be taken into account when developing electrically tunable microwave devices.
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4 Views
It is shown that in semiconductor structures with a low quantum dimension, it is possible to obtain the required potential relief for quasiparticles by changing the sizes of the structure elements. By using the example of a resonant-tunneling diode formed from planar nanowires of various cross-sections and lengths, it is demonstrated how such changes affect the potential for electrons and the electrical characteristics of the device. The considered approach is based on the effect of dimensional quantization of the energy of quasiparticles in solids.
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5 Views
A study of radio tube technologies developed in Germany during the First World War has been conducted. The designs of tube triodes from various German companies and the features of their production and application in radios and audio amplifiers are considered. The invention of a multiple tube by Sigmund Loewe and the technology of its manufacture are considered in detail. It is shown that Manfred von Ardenne has nothing to do with this invention.
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25 Views
The article states the need for new methods of visualization of information flows, one of which is infographics, and notes the insufficiency of its use in the historiography of science and technology. The reasons for this are the weak use of effective methods of sys-tematization (periodization and classification) of content, as well as the lack of methodology for such presentation. The main provisions of the study are briefly considered, in which the problems of systematization are solved using some provisions of the general theory of systems by V. N. Sadovsky.
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21 Views
This paper considers a threat scenario of unauthorized eavesdropping in a peer-to-peer network, where routes between the initiator node and the recipient node pass through two intermediate nodes. It is shown how the compromise of one or several nodes affects the share of routes that can be intercepted by an attacker and how this relates to the total number of possible routes. Formulas are obtained for calculating the number of intercepted connections, and probabilities of successful interception and unsuccessful connection are determined, reflecting the system’s vulnerability.
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15 Views
It is shown that if the complex coefficient of transmission of the matched filter is determined according to the criterion of the minimum output noise variance at a fixed reference value of the output signal, then an increase in the signal-to-noise ratio at the output of such a filter is possible by appropriate selection of the energy spectrum of the signal. The choice of the energy spectrum of the signal is due to the type of power spectral density of the input noise.
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34 Views
The article examines the main stages of scientific and social activity of the famous Russian scientist Viktor Mikhailovich Pestrikov, provides a bibliography of his works in such areas as aging, destruction and diagnostics of solids; history of radio electronics, information technology; applied mathematics; general history. The article is illustrated with photographs from 1986–2011.
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29 Views
The results of electrodynamic modeling of the conducting properties of sections of strip-type microwave transmission lines containing surface gammadion configurations deposited on the back side of the conducting transmission line are obtained for one single-pass gammadion and a separately configured cascade of them, in comparison with the parameters of a conducting section with a two-pass gammadion.
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8 Views
The article presents the results of an experimental study of the absorption properties of carbon nanostructured films in the S-band. The dependence of the transmission, reflection and absorption coefficients on the resistance of carbon samples with an absorption peak of an incident electromagnetic wave in the resistance range of 350–400 Ohm is shown.
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17 Views
The article studies the change in the statistical properties of measurements of the Z-component of the Earth’s magnetic field, carried out on mutually distant magnetometers during 15 days before the earthquake of February 6, 2023 in eastern Turkey. The differences in the corresponding statistics associated with both the difference in directions to the epicenter and the significant difference in distances to azimuthally close magnetometers are analyzed.
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47 Views
This study is based on the analysis of the current state and main trends in the design, synthesis and application of various transparent electrodes, including transparent conductive semiconductor oxides, metal ultrathin films, partially filled structures and multilayer oxide/metal/oxide structures.
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37 Views
The current state and prospects of development of the component base for ultra-high-speed electronics with low power consumption are considered. Approaches to the design of solid-state electronic devices based on nanowires that can be used in future digital electronics and their constructions are proposed. Estimates of the expected characteristics of these devices are presented.
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43 Views