ISSN 0021-3454 (print version)
ISSN 2500-0381 (online version)
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Summaries of the issue

INFORMATION TECHNOLOGIES AND SYSTEMS

253
A comparative analysis of accuracy of amplitude and phase measurements for complex and analytical signals is carried out. It is shown that retrieving of analytical signal with the use of the Gilbert transform, introduces errors when quadrature component is derived. Relative errors of measured amplitude and phase values are calculated in a wide range of values of the ratio the average frequency to the width of the signal spectral density, for the cases of amplitude and phase modulation of carrying oscillation.
SIGNAL PROCESSING OF SATELLITE NAVIGATION SYSTEMS WITH QUADRATURE MULTIPLEXING AND FREQUENCY DIVISION Andrey P. Aleoshkin , Vladimir S. Bakholdin, Denis A. Gavrilov , Lekontsev Dmitry A.
261
New algorithms for processing of signals from global satellite navigation systems are proposed. The algorithms increase the system resolution, accuracy of the time delay estimation, and improve the signal-to-noise ratio in the problems of navigation, signal detection and recognition. An estimate is derived for accuracy of navigation problem solution with the use of differential measurements. Results of experimental processing of GLONASS signals with frequency division multiplexing are presented to demonstrate the increase in signal-to-noise ratio when the algorithm of joint processing of signal from two navigation spacecraft is applied.
METHOD OF ATMOSPHERIC MODEL REFINEMENT FOR BALLISTIC SUPPORT OF ROCKET-CARRIER LAUNCHES Arseniev Vladimir N., Alexander B. Kuznetsov, Yadrenkin Andrey A.
268
The problem of refinement of atmospheric model used for ballistic support of rocket-carrier launch is considered. The vertical profiles of thermodynamic parameters of the atmosphere and wind velocity are presented in the form of canonical decompositions with known mean values, mean square deviations, and coordinate functions in node points along the vertical coordinate. The proposed approach allows approximating the specified characteristics of atmospheric parameters dispersion with the model ones.
STOCHASTIC FILTERING FOR INTER-SATELLITE MEASUREMENTS IN GREAT-CIRCLE TRAJECTORIES Sergey V. Sokolov, Sergey M. Kovalev, Vladislav V. Kamensky, Pavel A. Kucherenko
275
The problem of stochastic filtering of inter-satellite measurements used to identify the current position of the navigation satellites is considered. A filtering algorithm for data exchanges between satellites is proposed. The data include parameters of the satellite trajectories and ordinates estimates; the algorithm covers transmission and reception of navigation messages; determining pseudo-ranges and pseudo-speed of selected satellites relative to other ones; solution of the system of the filtering equations and evaluation of current coordinates of the satellites. The proposed approach to stochastic estimation of motion parameters allows to determine the current coordinates of the navigation satellite just on board using simple techniques of radio and laser measurements, thus reducing computational load on consumer receivers and telemetry tracking stations. More than that, the described method is reported to improve the overall accuracy of navigation due to the higher accuracy of inter-satellite measurements made in space as compared to telemetric measurements affected by to atmospheric disturbances.

INSTRUMENTS AND SYSTEMS OF AUTOMATIC CONTROL

282
A solution to the problem of robust control over gas-lifted oil wells operation is proposed. The described solution is suitable for parametric uncertainty, unknown initial conditions, and necessity of output signal (volume flow at the well outlet) measurement. The model of the process is represented by ordinary differential equations derived from the Navier-Stokes equations using the straight lines approximation. The control signal is variation of flow rate of the gas supplied to the well. A modified back-stepping algorithm is used for control algorithm synthesis. Implementation of a single filter for the system condition by the control signal and straightforward control laws obtained using real differentiating element, allow to simplify the calculations and implementation of the control system. The trajectory which is a solution to linear-quadratic model problem is taken as a standard action Simulation results are presented to demonstrate the effectiveness of the proposed scheme which is robust to parametric perturbations caused by variations of physical and chemical parameters of the process.
DATA TRANSLATION BETWEEN EDA AND MCAD SYSTEMS Romanova Eva B., Trifonova Tatiana A.
288
The possibility of data transfer between systems of automated design of electronic devices (Electronic Design Automation, EDA) and systems for mechanical components design (Mechanical Computer Aided Design, MCAD) is studied experimentally. The problems of data exchange between the systems are investigated, ways of overcoming the difficulties are proposed. Operational capabilities of systems related to data transfer are considered, advantages and disadvantages of methods of data translation are described, and possible causes of errors are analyzed. Recommendations aimed at optimization of data transfer between the systems are formulated. The experimental use of the recommendations by Abeo Ltd in development of some tens of various electronic devices is reported to reduce the time of manufacturing preparation, improve the data transfer correctness, and therefore to increase the quality and reduce the cost of the production.
294
A relatively simple analytical model of current gain dependency on collector current of transistor module produced on the base of identical devices (Darlington pair) or different (complementary pair) types of conductivity is proposed. The operation conditions for the transistors constituting these modules are defined. The possibility to define a generalized electro-physical parameter of the emitter junction and the lifetime of minor charge carriers in the basic areas of input transistor modules is demonstrated. The developed model is presented in the form convenient for determination of static characteristics of other modules such as composite transistors with additional symmetry. Comparison of the theoretical results with experiments is carried out.

OPTICAL AND OPTO-ELECTRONIC INSTRUMENTS AND SYSTEMS

IMPACT OF ATMOSPHERIC TURBULENCE ON POTENTIAL ACCURACY OF PULSED LASER RANGEFINDER Zvereva Elena N, Lebedko Yevgeny Georgievich, Trifonov Kirill V., Le Vu Dinh
300
The effect of atmospheric turbulence on the RMS variation of pulsed signal time delay is considered. The variation is responsible for the root mean square error of pulsed laser rangefinder and therefore determines the potential accuracy of range measurement. The probability density function for the time delay values and the mathematical expectation of the root square variation of the laser pulse arrival time are evaluated.
PREVENTION OF IMAGE TILT IN PLANE MIRROR OPTICAL SYSTEMS Burbaev Amir M., Nizhegorodova Kseniya V.
306
Reasons for tilt of image in plane mirror projecting (indication) systems of measuring instruments are considered. Reasons for image tilt in the systems are analyzed. A method is developed for checking the mirrors arrangement on the system design stage. The proposed approach is based on vector-matrix representation. Practical recommendations for system designer are formulated.

HEAT REGIMES AND RELIABILITY OF INSTRUMENTS AND SYSTEMS

MEASURING DEGREE OF BLACKNESS OF SAMPLE SURFACE BY THE MONOTONIC HEATING METHOD Lapovok Yevgeniy V., Khankov S.I., Mosin Dmitry A., Pen’kov Maxim M., Urtmintsev Igor A.
311
A method for measuring blackness degree of sample surface in a small cryogenic-vacuum chamber is proposed. Physical and mathematical models of the measuring unit are described. The operation temperature range for blackness degree measurement is defined by the temperature of the cryogenic screen, the film electrical heater power, and duration of heating process. It is shown that for copper samples of 1 mm thick and 2 cm diameter at consumed electric power of a few tenths of a Watt and the screen temperatures from 80 to 150 K, the minimal measurement error is achieved at the processing time from 10 to 20 minutes. The proposed method is reported to reduce the processing time for blackness measurement for two orders of magnitude as compared with measurement in stationary thermal mode. In the proposed method, the specified constant value of the power depends slightly on initial  temperature of the sample. An important advantage of the method consists in significant saving of energy consumption for the screen cryostatting due to reduction of the time of elementary measurement.
DEPENDENCE OF THERMAL CONDUCTIVITY OF SILICONE-BASED COMPOSITE ON VOLUME CONCENTRATION OF BORON NITRIDE Mikheev Vladislav A., Sulaberidze Vladimir Sh., Mushenko Vasily D.
317
Composite material on the base of silicon with boron nitride is considered. Special features of the composite thermal conductivity dependence on volume concentration of the filler are studied experimentally. The results show that at 20°С thermal conductivity changes by a factor of 2,5 from 1,46 W/(m·K) to 4,10 W/(m·K), when BN comprises ≈22 vol.%. An explanation for the obtained results is offered on the grounds of percolation theory and the impact of the filler dispersity on the effective thermal conductivity of the composite. The percolation effect appears to be the stronger, the higher is the difference between the studied characteristic of the filler and the binder; example of model system of paraffin + graphite is presented as an illustration. 
323
Automation of commercially available thermal conductivity meter of construction materials ITSM-1 is carried out. The performed analysis of design of thermal unit of ITSM-1 make it possible to create an assembled electrical circuit of heat meters with a standard electrical resistor coupled with the AK-9.02 system of data collection and processing. Software for the conductivity meter calibration and measuring is developed as an application for ITSM-1 using Borland Delphi 7 for Windows. The instrument constant (thermal conductivity of the heat meters) is determined on the base of calibration with two standard samples of thermal conductivity made of LK-5 and Plexiglas.

BRIEF NOTES

328
Using transistor modules from devices with different types of conductivity (composite-based transistors with additional symmetry) as the examples, general applicability of the existing model for calculation of the ratio of the current gain to collector current is confirmed.