**NAVIGATION AND
HYDROGRAPHY №49/2017**

**Exploration
of the Possibility to Build the Platformless Gyroazimuth with Incomplete Number
of Gyro Measuring Devices. **Y. I. Binder. – Navigation and Hydrography. –
2017. – No. 49. – Р. 7–20.

The possibility to organize the gyroscopic course indication using only one oriented angular velocity sensor and triad of accelerometers at the cost of using the information about the linear speed of the object, is considered. The effectiveness of the proposed method of the course correction is considered. The results of tests of the experimental unit on the moveable platform are presented.

Key words: two-axis angular velocity sensor, gyro azimuth, course correction, lag, coordinates.

**Evaluation
of Errors in Transition from the Global Geocentric Co-ordinate System ПЗ-90.11
to the other Reference Co-ordinate Systems to Take them into Account in the
Algorithms of the Receiving Satellite Navigation Equipment. **V. V.
Gavrilov, Y. S. Dubinko. – Navigation and Hydrography. – 2017. – No. 49. – Р. 21–31.

The co-ordinate basis of the Russian Federation is presented as a reference co-ordinate system built as a geocentric geodetic network. The position of the determined points on the surface of the Earth relative to the co-ordinate basis can be obtained in the form of the spatial rectangular or geodetic co-ordinates or in the form of the planimetric rectangular co-ordinates and altitudes. As the 1990 Earth Parameters introduced in 1990 differ from ПЗ – 90, ПЗ – 90.02 and others used previously, it is necessary to determine the volume of additional design of the satellite navigation receiver. For this aim, the following points are treated:

– The structure of the ephemerides information transmitted by the navigation satellite equipment as applied to ПЗ – 90.11 is considered.

– The algorithms to calculate of the user co-ordinates and take corrections to the co-ordinates into account when passing to another reference ellipsoid (datum) are determined.

– The errors in co-ordinates recalculation from ПЗ – 90.11 to ПСС and take them into account in the other co-ordinate systems are evaluated.

Key words: transformation of geocentric co-ordinates, system of co-ordinates, clements of transformation, formulas of transformation, satellite navigation systems (SNS).

**On Corrections of Navigation Parameters of Astronavigation System during
its Operation in IR Spectrum.**** **V. N. Kostin, A. V.
Lavrentyev. – Navigation and Hydrography. – 2017. – No. 49. – Р. 32–37.

The possibility of correcting the navigation parameters by means of astronavigation system, using the celestial bodies in IR spectrum in operation is considered.

Key words: navigation parameters, astronavigation system, IR spectrum.

**Employment
of Microwave Radiometry Method to Take Account of the Delay of the Satellite
Navigation System Signals by the Humid Component of the Atmosphere. **D. M.
Karavaev, G. G. Shchukin,

V. P. Sviridov. – Navigation and Hydrography. – 2017. – No. 49. – Р. 38–45.

The prospects for employment of microwave radiometry method to solve the problems of account for accounting the delay of radiowaves in troposphere due to the humid component are considered. The expediency of fitting the GLONASS system with microwave radiometers is shown.

Key words: radiometer of water vapour, water content of atmosphere, tropospheric delay of radiowaves, global radionavigation system.

**Possible
Ways to Increase the Accuracy of Determining the Position Co-ordinates and
Speed of Autonomous Underwater Vehicle by Hydroacoustic Navigation System
Operating at Long Range. **N. Soloshchev, A. A. Yakushev, S. A.
Yaroshenko, V. P. Lenkov, Y. N. Morgunov. – Navigation and Hydrography. – 2017.
– No. 49. – Р. 46–50.

The possible ways to increase the accuracy of determining the position co-ordinates and speed of Autonomous Underwater Vehicle (AUV) by long-range hydroacoustic navigation system using the complex wide-band sounding signals are considered. It is shown that to increase the accuracy of fixing the position and speed of AUV, it is necessary to know the velocity of hydroacoustic signal along the way between the transmitter and receiver, to use the reference generators corrected by the data of the global navigation satellite systems GLONASS/GPS in onboard receiver and transmitter and to use the extremely correlation methods of processing the measured range.

Key words: AUV, GLONASS, GPS, velocity of sound in the water, hydroacoustic navigation network.

**The
European Vertical Reference System and Datum for Sounding Reduction of the
Baltic Sea. **S. V. Reshetnyak, L. G. Shalnov. – Navigation and
Hydrography. – 2017. – No. 49. – Р. 51–68.

The results of the international project “Datum of the Baltic Sea” for unification of the vertical reference datum in the countries of the Baltic Sea, definition and practical employment of the European Vertical Reference System (EVRS) and European Vertical Reference Framework (EVRS) are considered. Using the materials of the Working Group for hydrographic datum of the Baltic Sea Hydrographic Commission, the Definition of the agreed Datum of the Baltic Sea (BSCD 2000) is presented and measures to be taken by the Baltic Sea countries for putting it into practice are considered.

Key words: the Baltic Sea, chart datum, average multiyear sea level, navigation chart, European Vertical Reference System.

**Some
Problems of Employment of Geoinformation Systems when Providing the Navy with
Geospatial Information. **Y. N. Zhukov. – Navigation and Hydrography. –
2017. – No. 49. – Р. 69–78.

The problems of providing the Navy with geospatial information based on geoinformation systems are considered. These problems are connected with diverse kinds of navigation charts and topographic maps, specific features of arithmetic operations on computers and visualization system of geospatial information by computer technology.

Key words: navigation charts, topographic maps, differing accuracy of co-ordinates, difference in heights and depths.

**Problems of
Determining the Optimum Relationship between the Pollution Levels of the Oceans
and Atmosphere. **H. G. Asadov, S. A. Askerova. – Navigation and
Hydrography. – 2017. – No. 49. – Р. 79–83.

The problem of calculating the mutual correlation function between the degree of pollution of the ocean and atmosphere ecosystems by some pollutant in increasing time intervals, taking into account the influence of the first ecosystem on the state of the second system, is formulated and solved. It is accepted that due to assimilation processes in the water medium, part of the pollutants in the ocean waters is not involved in the correlation relationship. The method of calculation of the assimilation capacity of the water areas for the case of limited summary pollution coming to the first ecosystem during all intervals, is optimized. It is shown that with increasing length of the considered intervals, the degree of correlation of pollution levels in considered ecosystems is increased.

Key words: correlation, assimilation, ecosystem, optimization, pollution, ocean, atmosphere.

**Method of
Constructing the Uniformly Distributed in Space-Time Points of
Hydrometeorologic Observations Characteristics. **Y. N. Zhukov –
Navigation and Hydrography. – 2017. – No. 49. – Р. 84–93.

A new method of determining the most uniform points of time-space-time co-ordinates obtained when measuring the hydrometeorologic characteristics is proposed. The method can be used both for reconstruction of fields by means of the objective analysis and the choice of the measurement points representative for statistical calculations using the point data files. In the article all the necessary relationships and numerical parameters for program realization are presented.

Key words: uniformly distributed points, uniformity of hydrometeorologic measurements, objective analysis.

**Aleksandr
Ivanovich Sorokin (1924-2017). A Short Feature-Story of Scientific, Pedagogic and
Public Activities. **N. N. Neronov. – Navigation and Hydrography.
– 2017. – No. 49. – Р. 94–99.

The article contains the short description of the main stages of the scientific activities of A. I. Sorokin, his work in the sphere of hydrography, geophysics, cartography, limnology and mathematics in the period of his service in GNINGI, ROC, N. G. Kusnetsov Naval Academy and RAS Institute of Limnology.

Key words: hydrography, limnology, science, biography.