Статьи журнала - Siberian Aerospace Journal
Все статьи: 341
Impedance and dielectric properties of Bi2Sn2-xFexO7 stannates
Статья научная
Bismuth stannates Bi2Sn2–хFeхO7, х = 0,1; 0,2, which reveal the properties of multiferroics, are investigated. The mechanism of interaction between dielectric and electronic subsystems is studied, based on measurements of electrical resistance at alternating current, impedance, capacitance and dielectric loss tangent in the temperature range 100–600 K at frequencies 102–106 Hz. From the comparison of dielectric permittivity and the reactive component of impedance, the paramagnetic contribution of electrons to the dynamic magnetic susceptibility was established. Impedance jumps on temperature were detected as a result of changes in structural characteristics. The temperature dependences of the permittivity are described in the Debye model. The activation character of relaxation time and two relaxation channels are found. The activation energy of electrons in the migratory polarization is calculated.
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Статья научная
Creating the spacecraft propulsion systems with high energy efficiency and minimal weight and size parameters is an urgent scientific and technical task of the domestic rocket engine industry. At the same time, requirements are put forward to optimize the cost and time of design, development and manufacturing of engines, as well as environmental safety at all stages of the product life cycle. In this regard, it is proposed to use advanced laser 3D printing technologies (additive technologies) from metal powder using CAD models of engine parts in the production of space low thrust rocket engines (LTRE). Laser melting technology on modern 3D printers makes it possible to produce complex monolithic engine structures without the use of labor-intensive and resource-intensive operations of machining, welding, and soldering, as well as a significant reduction in the volume of fitting and assembly operations, control and measuring work, and a decrease in the influence of some non-production factors. The article discusses issues of practical application of promising technologies in the creation of LTRE. The results of fire tests are presented, which will be used to refine the previously developed calculation models of oxygen-hydrogen LTRE when creating advanced rocket engines for spacecraft. The object of the study was an experimental sample of LTRE with a nominal thrust of 150 N using gaseous propellant components oxygen and hydrogen, developed and manufactured using additive technology. The experimental LTRE is considered as a prototype of the engine for orientation, stabilization and launching of the oxygen-hydrogen upper stage. The purpose of the work is to study the effectiveness of previously unexplored design solutions for organizing mixture formation and cooling of an oxygen-hydrogen LTRE, to determine their influence on the perfection of the working process and the thermal state of the engine chamber. Fire tests were carried out in single switching mode with a duration sufficient for the LTRE chamber to reach a stationary thermal regime, with the determination of the energy characteristics and thermal state of the structure.
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Improvement of the construction technique of substitution blocks for symmetric encryption algorithms
Статья научная
As it is known, block symmetric encryption algorithms are widely used to ensure information confidentiality. The resistance of encryption algorithms to the most common types of cryptanalysis is determined the quality of the blocks of substitutions. In the present work, the development of a methodology for constructing substitution blocks is being continued. In the first approach, Boolean functions with given cryptographic properties are used as component functions of substitution blocks. Previously, one of the authors proposed a reasonable methodology for the phased selection of Boolean functions for construction block. In this paper, in addition to such cryptographic properties of Boolean functions, such as: balance, possessing a strict avalanche effect, possessing correlation immunity, for the first time the nonlinearity distances of the first and second orders of Boolean functions are considered simultaneously. A study of the full set of Boolean functions of four variables was conducted. The result of it is the optimal set of Boolean functions for building substitution blocks when encrypted with the GOST 28147-89 algorithm. In the second approach, the substitution block are determined by an irreducible polynomial over the Galois field, such a scheme, used in the Rijndael encryption algorithm, is considered to be strong. The growth of calculating power of the computer necessitates an increase of the cryptographic strength of encryption algorithms. The authors have proposed substitution blocks for each round of the Rijndael scheme, based on different irreducible polynomials. A study of compositions representing a different combination of specially selected irreducible polynomials for ten rounds was carried out and the optimal set of polynomials with the best values of the encryption quality indicators by the Rijndael scheme was obtained.
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Статья научная
To date, the problems associated with the safety of unmanned aerial vehicles (UAVs) are quite acute. As a rule, when it comes to commercial small-sized UAVs, wireless communication channels are used to con-trol them. Most often, communication is implemented at a frequency of 2.4 GHz using the Wi-Fi protocol. Such a UAV is quite easy to detect by analyzing the radio frequency range or the data link layer. An attack-er, however, may not even have specialized equipment and use open source software. The detected UAV becomes the target for attacks. If it is known that the UAV operates as a wireless access point, then all Wi-Fi-specific attacks become relevant for the UAV. In this study, it is proposed to use the technology of creat-ing false information fields as the first line of defense to increase the resistance of the UAV to attacks. This technology will allow to hide a legitimate UAV communication channel behind a lot of fake ones. The goal is to create fake access points with the characteristics of real ones and emulate data transmission over the channels on which these access points are deployed. In addition to the fact that the technology allows to hide a legitimate UAV communication channel, it will also allow to mislead the attacker. It is important to make the intruder think that not a single UAV is approaching him, but a group. If the intruder attempts to attack decoys, attacker will compromise himself and be able to be detected. Thus, you can use the UAV as a bait. As a result of the pilot study, channels were identified on which the creation of fake access points is most effective. Using small computing power and the necessary antenna, you can achieve high results. This article demonstrates the effectiveness of creating 9 fake access points. A comparison was also made with real wireless network traffic. We can say that the emulated activity is quite close to the real activity.
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Статья научная
The formation of an incommensurate three-dimensional magnetic order in an antiferromagnet as a re-sult of a strong correlation between holes and localized spins is studied. The spectrum of spin polarons, the spin density wave, and the wave vector of the structure are calculated in the Kondo lattice model. The magnetic system is considered in the adiabatic approximation, the sublattice magnetization and spin-spin correlation functions are presented in the mean-field approximation. The Fermi energy and s – d interaction energy are calculated. The heat capacity and heat capacity anomalies due to spin polarons are determined. Anomalies in the temperature dependence of conductivity and in optical conductivity in the lowenergy region are found.
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Increasing software reliability of a distributed control systems
Статья научная
The article considers a method of assessing and improving main parameters of the computer network efficiency. Reliability is the main criteria for ensuring the required performance of distributed control systems. To improve reliability of the computer network hardware and software redundancy are used. Software redundancy requires new versions to be developed for software modules in which failures are likely to occur. The article considers the N-version programming and recovery block as methods of introducing software redundancy and, taking the need to develop multiple versions of the same software module into account, estimates the costs of network software development. To implement the proposed approach article presents mathematical reliability model that takes into consideration the architecture of a computer network software and the labor costs that its development is going to require. This model becomes a basis for a software created to research computer network software reliability, which allows finding the dependence of network software reliability on the number of one of its software module versions. Comparison of the dynamics changes of reliability indicators and labor intensity of software development indicated a sufficient amount of software module versions that need to be developed. The article concludes by pointing out the importance of determining the labor intensity of network software development and of its usage in the design of a computer networks in which reliability is increased through software redundancy.
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Increasing the capabilities of a test ballistic missile to separate test objects
Статья научная
The subject of this study is the trajectory characteristics of the long-range test ballistic missile (TBM). The purpose of the study is to increase the capabilities of TBM in separating test object (TO). At the same time, as a generalized quantitative measure of this increasing, the post-boost vehicle (PBV) fuel reserve consumed for separation of TO is studied. The design-ballistic task of rationalizing the distribution of the available fuel of the TBM PBV between the following main characteristic section of its flight has been set and numerically and analytically solved: final sustainer stage undershoot compensation; turns with subsequent angular stabilization, retreats and lead away; TO disconnection (separation section). As a result, it is shown that without reducing the quality of TBM launch tasks, it is permissible to redistribute the consumed fuel of the PBV between these section relative to the distribution for a standard ballistic missile (SBM), leading to a significant increase in its reserve consumed in the section of disconnection of the TO (when flying along the ballistic vertical). At the same time, the purpose of the study is achieved – the capabilities of the TBM in the separation of the TO are increased, which, while direct planning of launches is evaluating, can be expressed in an increase in the number and/or total mass of the TO and/or an increase in speed or time intervals in the order of sequential disconnections of the TO. The given numerical examples (using a converted three-stage SBM as a TBM) also show a significant dependence of the amount of fuel increment of the PBV consumed at the TO disconnections of the trajectory conditions of test launches (the corresponding initial data (ID) for calculations are borrowed from the author’s previously published work): length of the route; kinematic parameters of launch at the moment of independent PBV flight beginning determined by the launch task. During the study, methods of flight theory and design ballistics of LR (long range) missiles were used. As a conclusion, it can be noted that the considered task and methods for its solution can be useful (of course, taking into account the necessary specialized improvements) in works of the executive ballistics level when planning and evaluating the result of TBM launches.
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Increasing the period of active use of on-board electronic equipment of spacecraft
Статья научная
For electronic equipment of space systems, and primarily memory devices, the task of protection from the effects of ionizing cosmic radiation and other external factors that distort stored and processed information is relevant. This paper proposes a holographic coding method that allows to restore information in the event of a large number of errors. The method is based on recording into memory, instead of the original digital hologram data, a virtual digital object corresponding to a data block. The divisibility property of a hologram is used, which makes it possible to reconstruct a recorded data block from its fragment. The achieved level of noise immunity is determined by the size of the hologram. For an 8-bit data block, recording a 256-bit hologram provides information recovery if 75 % of the recorded hologram is lost. The developed decoder corrects a package of dependent (grouping) errors that distort all bits of the hologram. The number of random independent errors that the decoder corrects can be up to 40 % of the recorded information. The information storage system, resistant to ionizing radiation, is a memory array of increased capacity, taking into account the selected redundancy factor, and a memory controller that performs holographic encoding when recording information and decoding with automatic error correction when reading information. The operating algorithm of the controller itself can be implemented in the form of a programmable logic integrated circuit, or stored in a read-only memory device that is not affected by ionizing radiation.
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Increasing the positioning accuracy of the GLONASS system
Статья научная
The accuracy of determining coordinates in global positioning systems is determined by the number of satellites simultaneously visible to the consumer's navigation equipment. Over most of the earth's surface, there are up to 11 GLONASS satellites above the horizon at the same time, but the signal-to-noise ratio in the communication channel required for error-free information reception is often ensured only for 2-4 satellites. To improve the positioning accuracy, it is proposed to use the holographic noise-immune coding method based on the holographic representation of the digital signal. The message coding process is a mathematical modeling of a hologram created in virtual space by a wave from the input signal source. It is shown that the holographic representation of the signal has significantly greater noise immunity and allows restoring the original digital combination when most of the code message is lost and when the coded signal is distorted by noise several times exceeding the signal level. The studies have shown that the introduction of holographic coding in the GLONASS satellite communication channel will enable consumer navigation equipment to receive information from a larger number of satellites, which will significantly improve the positioning accuracy. In a common situation where the required signal-to-noise ratio is maintained for only 4 GLONASS satellites, the positioning error exceeds 10 meters. Using holographic coding in the same situation, information from 9 satellites will be decoded without error, and the positioning error will be about 2 meters.
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Статья научная
Liquid-propellant rocket engines (LPRE), operating according to a gas-free generator scheme, are used for the upper stages of launch vehicles and upper stages. In engines of this scheme, only cryogenic fuel is used, which provides a high engine STI. Also, a distinctive feature is the absence of a gas generator, the combustion generators of which feed the turbine of the main turbopump unit. In the gas-free LPRE scheme, the turbine is driven by gas-return hydrogen heated in the cooling loop. Therefore, the high parameters of the LRE, such as the pressure in the CC, the thrust of the engine and the specific thrust pulse depend on the effective heat removal from the firing wall of the combustion chamber and the intensification of heat ex-change in the cooling path. There is a number of solutions that allow to increase the amount of heat transferred to the refrigerant in the inter-shirt space. Therefore, the search for an optimal cooling scheme and promising design solutions for the intensification of heat transfer in the engine cooling path will allow us to determine the high param-eters of the LPRE. This article discusses the effect on the thermal state of the combustion chamber of the gas fins installed on the firing wall of the engine. Gas fins belong to the developed heat exchange surfaces and increase the area of the side surface of the combustion chamber. With the help of the developed mathematical model of the cooling chamber of a gas-free LRE, extremes in the intensification of heat exchange in the cooling path have been identified. The dependences of the specific thrust impulse of the engine on the pressure in the combustion chamber and the geometric dimensions of the engine are also obtained.
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Influence of a constant electric field on the adsorption purification of water from iron ions
Статья научная
Using electrochemical action (ECA) to treat water was first proposed in UK in 1889. At present, many methods of ECA are known (electro flotation, electro coagulation, electro osmosis, electrophoresis, etc.). In the production of rocket and space technology, galvanic technologies are used, as a result of which waste water is contaminated with metal ions. Known methods of wastewater treatment do not allow to ensure the maximum permissible concentration of metal ions in treated water, or are expensive or difficult to operate in industry. Iron ions are among the most polluting components of wastewater of most industries. So increased control and the development of effective methods of wastewater treatment are necessary. Iron affects the intensity of phytoplankton development and the qualitative composition of microflora in reservoirs. The toxicity of iron compounds in water depends on the hydrogen index of water. The alkaline environment dramatically increases the risk of fish poisoning, as in such conditions, iron hydroxides are formed, which are deposited on the gills, clog and corrode them. In addition, iron compounds bind oxygen dissolved in water, which leads to the mass death of fish and other hydrobionts. The article presents the method of conducting experiments, the methods of sorption, electrochemical and combined water treatment, including electrochemical action and adsorption. The results of studies of these methods of water purification from iron ions are presented. The dependence of the degree of purification on the electric field strength, interelectrode distance and water treatment time is revealed. With an electric field strength of 5.16 V/mm, a temperature of 20–22 °C using quartz sand as an adsorbent and a processing time of 1 minute, the concentration of iron ions decreased from 2.5 to 0.25 mg/l (at MPC = 0.3 mg/l). The proposed combined cleaning method requires inexpensive and affordable materials and is easy to operate.
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Статья научная
The properties of a solid solution of thulium-substituted manganese sulfide prepared by melting the ini-tial pure samples of manganese sulfide and thulium sulfide are studied. X-ray diffraction analysis was car-ried out. The face-centered cubic lattice is determined, and the decrease in the intensity of the peaks is found. Dielectric permittivity was measured in the frequency range 102–106 Hz and temperatures 300–500 K in magnetic fields up to 12 kOe in TmxMn1-xS solid solutions (0 < x < 0.15). From the frequency depend-ence of the permittivity, the relaxation time and the relaxation mechanism of the dipole moments are found. The leakage current is excluded, and the contribution of migration polarization due to charges in the re-gion with chemical phase separation is estimated. The real and imaginary components of the permittivity of TmxMn1-xS samples are described in the Debye model. The maximum of the imaginary component of the permittivity shifts towards higher frequencies upon heating, and the relaxation time is described by the Ar-rhenius function. Dielectric losses are caused by electron-phonon interaction. The frequency of the crosso-ver from Debye relaxation to relaxation conduction associated with the absorption and emission of pho-nons is found. The crossover frequency increases as the sample is heated according to a power law. In a magnetic field, the permittivity decreases and the largest change of 2.5 % is achieved at T = 450 K. At oth-er temperatures, the magnetocapacitance does not exceed 0.5 %. The shift of the maximum of the imagi-nary component of the permittivity to low frequencies in a magnetic field leads to a change in the sign of dielectric losses from positive to negative. A qualitative difference in ε(ω) is established in the vicinity of the concentration of thulium ion flow through the FCC lattice, where the permittivity is not described in the Debye model and there is no magnetocapacitance. The mechanism for reducing dielectric losses in a mag-netic field is determined.
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Influence of plasma jets of electric jet engines on spacecraft functional characteristics
Статья научная
The issues of compatibility of correcting electric jet engines (EJE) and large-size transformable antennas (LTA) used in high-orbit communication satellites are considered. The paper deals with the erosive and polluting effect of EJE jets interacting with knitted mesh material (grid mesh), which is used for manufacturing LTA reflectors. The erosive effect of the EJE jets on the LTA mesh is characterized by the fact that the angles of ions incidence on the surface of the threads in the mesh are in the range from 0 to 90, i. e. such effect takes place at practically any angle of ions incidence on the mesh surface. The research includes both mathematical description of physical processes and conducting a wide series of experiments, which makes it possible to achieve the necessary reliability of the results. It has been established that the effect of plasma jets of correcting engines can lead to significant sputtering of the reflecting coating from the surface of a large-size antenna reflector. The authors obtained experimental data on the degradation of the reflection coefficient of electromagnetic radiation from the mesh, depending on the degree of plasma jet influence. It was found that the sputtering of reflecting coating from the surface of threads does not significantly affect the reflection coefficient. The sputtering of the coating at the points of threads contact is much more significant. Strong dependence of the reflection coefficient on the type of mesh weaving was also found. The mechanism of sputtering products deposition on reflecting coatings of the thermal control system radiators was investigated. The results of calculations of the sputtering coefficient and the sputtering indicatrix of the reflecting coating applied to the mesh threads were obtained. The degradation of the functional characteristics of thermoregulatory coatings (TRC) during the deposition of thin films of gold, which is one of the possible materials for a reflecting coating, was experimentally determined. Estimates of the maximum permissible level of TRC contamination were obtained. It is shown that, subject to the relevant design rules, it is possible to use EJE and LTA together in high-orbit communication satellites.
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Статья научная
Due to the absorption of solar energy in chloroplasts – green plastids, solar energy is converted into the energy of chemical bonds. Studying the processes of photosynthesis and increasing its efficiency is relevant for the development of closed life support systems, during long flights in space as well. Chloroplasts are filled with stacks of highly ordered thylakoid membranes (grana). Pigment-protein photosynthetic complexes are located on the border of these membranes. For a long time, the structural characteristics of chloroplasts were not given due attention and they were studied as isotropic substances, but in recent years it has been shown that they have anisotropic properties and a high conversion coefficient during charge separation. In this work, an approach was proposed for a more accurate spatial determination of grana in plant chloroplasts and for determining the size of a single unit. Thylakoid membranes and the boundaries of the facet consisting of them are clearly visible in an electron microscope if the electron beam is directed strictly perpendicularly. It was noticed that when the stage is rotated, different regions of the membranes become either blurred or more distinct, which suggests that the grana in chloroplasts are not located in the same plane. Also, a comparison was made of the influence of different external conditions on the chloroplast structure of a plant, not only through a comparison of morphological characteristics, but also through numerical modeling and comparison of the objects spectral properties. For numerical simulation, periodic lattices were determined for the main structural units of chloroplasts of different samples. On the basis of these gratings, the transmission spectra were calculated using the transfer matrix method. Also, the obtained values of the electromagnetic wave along the lattice made it possible to calculate the graphs of the density of photon states. The results of the calculation method of plots of the density of photon states based on the structure of chloroplasts made it possible not only to assess the possible efficiency of photosynthesis, but also to directly relate these models to the external conditions affecting the plant.
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Influence of the magnetic field on transport properties of holmium – manganese sulfide
Статья научная
Holmium-manganese sulfide with giant magnetoresistance refers to new magnetic sulfide compounds of holmium and manganese that have the effect of giant magnetoresistance (i. e., with special magnetoelectric properties), which can be used as components of sensor technology, magnetic memory, and spintronics. The technology of manufacturing polycrystals HoXMn1-XS grown by crystallization from the melt of the obtained powdered sulfides with a purity not lower than 99,9 %, in glass-carbon crucibles and a quartz reactor in an argon atmosphere is presented. According to the results of x-ray diffraction analysis, HoXMn1-XS holmium-manganese sulfides have a HCC structure of the NaCl type. As the degree of cationic substitution increases, the unit cell parameter increases linearly with the concentration. No concomitant impurity phases are detected in the synthesized samples. To determine the state of the spin glass, magnetic moment measurements are conducted at several frequencies ω = 1 kHz, 10 kHz and 100 kHz. The dependence of magnetic characteristics on the frequency of measurements is found. The damping of the magnetic moment and its increase with a decrease in temperature is reviled, which is connected with the formation of metastable States. Measurements of electrical resistance without a field and in a magnetic field are conducted. Anomalies in the temperature dependence of the conductivity are found. A change in the magnetoresistance sign is detected with the increase of temperature below and above room temperature.
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Information-measuring system of pyrometric type for small-sized unmanned aircraft
Статья научная
A new trend of science and technology is now rapidly developing both in Russia and abroad – the development of miniature unmanned aerial vehicles. The key system of on-board control equipment (avionics) of an unmanned aerial vehicle (UAV) is the orientation system for determining UAV attitude relative to reference system. In small-size UAV, we can meet the application of strapdown attitude reference systems, magnetometric, pyrometric, video systems, etc. Rapid development of mini- and micro-UAVs requires the development of information-measuring systems (operating on different physical principles) in order to determine UAV attitude parameters in flight. With UAV mass and wingspan reduction, there are growing requirements for these systems, concerning the accuracy of positioning parameters and more compact dimensions. Manufacturing of most information-measuring and control systems of manned aircraft and heavy UAVs rely on traditionally used gyroscopes and accelerometers. They are complex fine-mechanics instruments of considerable power consumption, rather large size, weight and high cost. A significant improvement of the accuracy in UAV angular coordinates determination is achieved by integrating orientation systems of various types. The use of GPS / GLONASS signals also improves the accuracy and reliability of determining UAV angular coordinates and supplies the additional function of measuring its geographical coordinates.
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Infrastructure for collecting data and simulating security threats in the internet of things network
Статья научная
The implementation of the internet of things technologies in the rocket-space industry requires increased security measures for information and communication processes. Existing intrusion detection systems are unable to take into account the heterogeneity of the network structure and the scale of information circulating between devices. To solve this problem, intrusion detection systems use an anomaly method, which requires a large number of representative data sets. The authors have reviewed public datasets that can be used to build an anomaly detection system. They contain information from artificial simulation medium or isolated environments with simulated devices, include examples that are not directly related to the internet of things, and do not take into account the dynamic nature of traffic changes. In this paper, we present a new infrastructure that will avoid these drawbacks. It collects data on the functioning of a real Internet of Things network and allows testing its stability to typical attacks. We use the MQTT (message queuing telemetry transport) application protocol and software platforms that support information interaction based on the publisher-subscriber pattern. The infrastructure contains devices that monitor technological rooms with telecommunications equipment, brokers with various security policy set-tings, applications for data control and analysis, software agents for collecting network traffic and threat simulators that perform attacks on network nodes from single sources or in a distributed environment. Researchers will be able to use the data collected in the infrastructure for cybersecurity analysis to create reliable IoT-based solutions needed to implement this technology in knowledge-intensive space systems production.
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Статья научная
The possibilities of creating an innovative educational and scientific center for monitoring forest resources in Siberia on the basis of the Department of Space Facilities and Technologies of the Reshetnev Siberian State University of Science and Technology are discussed, with the aim of training highly qualified engineering personnel and conducting promising scientific research in the field of monitoring, modeling, forecasting and management of forest resources. Methodological solutions and algorithms for threedimensional modeling of forest structure and dynamics based on laser scanning data, digital aerial and space photography are proposed. These methods contribute to operational monitoring and can significantly reduce the cost of monitoring the condition and use of forest resources over the vast territory of Siberia. Remote sensing data is presented in the form of a geotransformed database and digital photo map, compatible in formats with computer-aided design systems and with the main geographic information systems – ArcView, ArcINFO, MapINFO. The innovative monitoring center will be used for operational state control and monitoring of forest management, the state of forest lands, forest management and forest inventory, solving problems of ecology and environmental management, geoecology, formation of a forest resource inventory, aerospace methods for studying natural resources and territories, information technology. Solving these problems will allow for the training of highly qualified specialists. The center's specialists plan to create information technologies for remote sensing of natural objects with the aim of import substitution of foreign software products. The main scientific directions of the created center: development and research of methods for system analysis of large-scale multidimensional remote sensing data based on nonparametric decision-making algorithms and parallel computing technologies; testing hypotheses about the distributions of large-volume remote sensing data based on nonparametric nuclear-type pattern recognition algorithms; detection of compact groups of large-volume remote sensing data corresponding to unimodal fragments of the joint probability density of multivariate random variables.
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Статья научная
Academician Mikhail Fedorovich Reshetnev is one of the outstanding scientists, designers and production organizers who stood at the origins of the development of rocket and space technology in our country and made a significant contribution to domestic and world cosmonautics. 2024 marks the 100th anniversary of his birth and the 60th anniversary of the first launch of the Kosmos-3 launch vehicle (LV), created under his leadership in the Krasnoyarsk Territory. The article discusses the main stages of design, development work, flight design tests and the launch of mass production of the rocket. It is noted that the creation of the PH was carried out mainly at the production base of the Krasnoyarsk Machine-Building Plant (Krasmash). The most important events related to the organization of the OKB-1 branch, which was then transformed into an independent OKB, are described in chronological order. The role of M. F. Reshetnev’s personality is shown. Reshetnev in solving complex scientific, technical, organizational and production problems of mastering new technology in the Siberian region, remote from the rocket, space and scientific centers of the country. Information is provided on innovative technical solutions developed under the guidance of M. F. Reshetnev during the creation of the Kosmos-3 launch vehicle and its subsequent modification. It is noted that M. F. Reshetnev in his scientific and technical activities constantly received the support of S. P. Korolev and M. K. Yangel, successfully cooperated with the largest design organizations headed by V. P. Glushko, A. M. Isaev, V. G. Sergeev and other well-known leaders and specialists of the rocket and space industry.
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Inter-satellite optical communication link
Статья научная
A two-level system of data transmission in the optical range is considered between a low-orbit spacecraft located in a sun-synchronous orbit and a repeater satellite located in a geostationary orbit. This topic is rather relevant due to the fact that the rapid development of remote sensing satellites resulted in the increase of the amount of transmitted information, which in consequence introduced new requirements for communication systems. The increase of data transmission rate and severization of requirements for communication systems contributed to the development of one of the most promising areas of space communications, based on the information transmission via a laser channel, due to a high energy concentration and a much higher carrier frequency. The prospects for the application of optical communication systems are designated by lower power consumption, dimensional specifications and the mass of the transceiver equipment of the optical range (compared to radiofrequency range systems). The article describes the solution of application of optical communication link between a low-orbit spacecraft and a repeater satellite. The main factors that contribute to the attenuation in the process of signal propagation along the route are presented and analyzed. A model of a communication channel between a low-orbit spacecraft and a repeater satellite is provided for a visual image. Two different approaches of mutual guidance and tracking of laser terminals are described for using beacons and without ones. EDRS foreign system is considered as an analogue. The estimation of the main parameters of the communication link is given. The communication system considered in the article will allow for greater carrier capacity of the data transmission in the optical range between the low-orbit spacecraft and repeater satellite. The application of this system will allow solving problems, including in the interests of any departments and structures of the Ministry of Defense of the Russian Federation, for which the rate of obtaining information is one of the basic requirements for a satellite communication system. The tasks of precise targeting of receiving and transmitting devices arising as a result of narrow beam patterns can be solved with current technical means.
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