Vol 14, No 6 (2013)

The report dwells upon the milestones on the way of creation of global space systems of the first and the second generations: scope and volume of work, workflow phases and implementation periods, main characteristics of satellites of this system. The authors present the main results of modernization of the space segment of the home global space navigation system of the second generation, obtained in the process of carrying-out the Federal Program “The Global Navigation System”. The report shows the main principal directions of development and modernization of the space segment of the home global space system, which are directed with the Federal Program “Maintenance, development and exploitation of the GLONASS system for the period of 2012-2020“.

The authors present the analysis of characteristic features of the existing orbital group of the GLONASS system and foreign global navigation satellite systems development trends, along with the elaborated approaches and standards for the development of the update structure of an orbit group. Different variants of the GLONASS orbital group update are analyzed, evolution and methods of the GLONASS orbital group compensation are investigated for the analyzed variants of the orbit group. Preliminary proposals for the GLONASS orbit group structure of the year 2020 are worked out.

The paper presents the time-and-frequency support (TFS) of Global Navigation Satellite System (GNSS) of GLONASS. The basic functions of GNSS GLONASS TFS are considered, the TFS technology realized nowadays in GLONASS System Control Center is briefly described, the analysis of TFS hardware/software complex operation and its results are introduced, TFS accuracy characteristics and the main ways of their update are presented.

“Laser GLONASS” is a complex of techniques and technical means, on the basis of which the GLONASS signal-in-space error will be radically reduced. Creation and full deployment of onboard and ground laser GLONASS systems may be recognized as an effective and asymmetrical response to the competing systems (GPS, Galileo, etc.) concerning provision of the space segment precision. Development of prototypes and production samples of onboard and ground laser equipment is foreseen by the «Maintenance, development and use of the GLONASS system for 2012-2020» Federal Program. The problem of laser GLONASS development and therefore achievement of the worldwide leadership in the field of potential ephemeris-timing provision is the real prospective of the nearest time.

The cost efficiency calculation models for communication satellites were developed considering two financing schemes: the government budget financing, and at the expences of bank crediting. For each of these schemes the cost efficiency indicesare formed: basic costs payback period and profitability index. Respective calculation methods for cost efficiency indices were developed for both financing schemes. There was proposed the constraint criterion for the cost efficiency factor existence range: the project profitability shall be no less than bank deposit profitability. Using the assesment results there were developed guidelines for the payback period restriction, that is less than one third of the satellite lifetime.

The authors present a comparative analysis of of the compliance of global navigation satellite systems (GNSS) augmentations current status with the future user requirements in positioning accuracy. The algorithm of precise positioning is proposed. Experimental studies of the complex algorithms based on the use of the existing system for differential correction and monitoring facilities are presented. On the basis of the research results the forecast of GNSS precise positioning systems development is made.

Results of research of the existing conditions of high-orbitał users navigation support by GNSS signals are given in article. The way of modernization of GLONASS system for increase of availability and accuracy of high-orbitał users navigation support is offered. The author shows the possibility of reasonable increase of availability and accuracy of high-orbital users navigation support in the area up to the heights of the Moon orbit, which opens the possibility of spacecraft autonomous navigation by GLONASS signals on the flight route from the Earth to the Moon and in the circumlunar orbit. The basic requirements to the directional diagram, the type of navigation signal and the power of onboard signal transmitting equipment for space users are presented.

We discuss the technique of study of the Near-Earth environment with Global Navigation Satellite System data by means of the total electron content and navigation satellites phase slips metering. We analyze global electron content data as well as the near-Earth disturbances influence on positioning with the use of Global Navigation Satellite Systems and present the details of the Siberian GPS/GLONASS receivers network implementation. Results of detection of ionosphere response to solar terminator and different intensity of earthquakes are shown as well

Basic results and perspective problems of the experimental and theoretical researches of the unsteady heat regimes of the GLONASS system spacecrafts are presented. A hierarchical approach to the mathematical modeling of the heat regime of the spacecraft is described. Mathematical models of precision thermal control of atomic frequency standards and spacecraft heat-loaded devices are considered. A description of the construction of the local precision temperature stabilization system using thermoelectric converters and hyper-heat conducting plates (flat heat pipes) is given. Calculations and experiments have shown that the local system allows to maintain the temperature of heat setting atomic frequency standards blocks in the range of 10-20 °C with accuracy of no more than 0,1 °C.

This work provides the 347K static sun sensor description based on the CMOS active pixel sensor and the super-wide-angle imaging system. The articledescribes the laboratory testing results for the sensor confirming the 2-axis orientation accuracy with the total error of 1 ', and the sensor steady operation when there were observed the partial screening of the sensor field of view by the SV structure elements as well as sunrays reflected from the SV structure or the Earth surface. To reduce the temperature effect for Sun angular coordinates measurement errors the titanium alloy was used for leans mount and algorithmic coordinate correction was introduced which take into account temperature sensor data of photodetector.

The problem of protection of spacecraft electronics against ionizing radiation is reviewed. The goal of the work is to develop and study the multiphase heterogeneous materials for shielding of spacecraft electronics on the geostationary orbit. The subject of the study is disperse-filled polymer composite materials and the objects of the study are the processes of interaction of electron radiation with the mentioned materials. The imitative irradiation method of samples of the composite materials was used in the study. Simulating of electron transmission through the samples of the composite materials was made with Monte-Carlo method. The results of the study demonstrate that shielding ability of the developed samples of the composite materials is no less than 30 % greater as compared with aluminum at the equal mass thickness. The developed composite materials can be applied in the systems of passive shielding of the spacecraft electronics on geostationary orbit.

The paper describes an innovative method of oversized transformable umbrella-type reflectors tuning in dynamic coordinate system tracing the reflector bearing structure behavior and adjusting to its geometry. The method enables to create a radio reflecting surface and a structure configuration closest to nominal value.

Gaps in mobile connections of mechanisms and effort transfer systems or movements lead to a mismatch between operating signal and reaction of the controlled object to this signal. Therefore the extended gaps become the defects of these structures. In this work the authors solve the problem of such gaps control by results of mechanisms resonant testing and systems. It allows to carry out defects detection without the structure dismantling and the subsequent instrumental inspection of its details sizes. The accelerations sensors are installed in connections places for defects detection. In a vicinity of the phase resonance frequency of the object control by the signals of sensors there constructed the Lissazhu figures, which are ellipses for ideal system. The gaps existence in connections is determined by deviations of Lissazhu figures from the elliptic form. The maximum deviations of Lissazhu figures correspond to the defective connections. Formulas for the assessment of gaps sizes by characteristic values of resonant frequencies are received. The efficiency of the developed technique is illustrated on the gaps control example in mechanical control wiring by the Su-34 plane. This technique can be used in the transmissions control of helicopters and cars, aircrafts mechanical control wiring.

The authors consider the steps involved in the creation and subsequent development of the multifunctional system of personal satellite communication and data transfer to spacecraft in low-earth orbits, the main technical solutions for the improvement of the technical characteristics of the system, increase consumer appeal and competitiveness with foreign analogues. Besides, the authors define the main consumer contingent system and present the refreshment dynamics of orbital grouping of the system until 2020.

The variants of alternate design, features, manufacturing technique, trying out and operation of cowcatchers, manufactured by JSC “ISS", are reviewed. The subject of this work is a problem of shipment of the automatic spacecraft without reducing the required reliability. One of the solutions is to reduce the negative impact of the mechanical stress on the automatic spacecraft using the amortization platform for their fixing in the transport container. Results of researches in the field of vibration isolation system design based on the flexible vibration-isolating elements are presented. The production technology and testing of the rope shock absorbers with the required vibration isolation characteristics are described. Results of practical application of the received results are reviewed. The results can be applied in the space-rocket field and other fields, where vibration protection means are used.

Methods of radiosignal modulation determination using in modern systems of radiofrequency spectrum control is described. Comparative analysis of different methods is carried out, results of imitation modeling is present.

This work has questions of organization television space bridges with usage of multifunctional space system relaying (MSSR) “Luch”. Here present general description, technical and operational description of system. Developed methodology use of MSSR “Luch” for organization television space bridges with ground consumers.