V.Ye. Vovasov – Ph.D. (Eng.), Associate Professor,

Moscow Aviation Institute (National Research University) E-mail: vovasov@list.ru

The problems of the technology of precision autonomous navigation definitions are systematized as they are important. The possibility of reaching the centimeter and millimeter accuracy of coordinate definitions is largely based on the use of phase measurements. However, the use of multi-valued GNSS phase measurements instead of unambiguous range-finding ones, although it leads to a significant increase in measurement accuracy, requires the solution of an additional problem – resolution of phase ambiguity. The ways to overcome this problem are indicated. The next most important problem, limiting the accuracy of coordinate determinations from GNSS signals, is the error of the ephemeris-time support of GNSS. It is noted that the results of absolute and relative determinations obtained by processing real measurements allow us to conclude that there is a stable tendency to reduce the error of the ephemeristime support. Nevertheless, in order to achieve maximum accuracy of coordinate determinations by means of satellite equipment, there is still a need to use the so-called accurate ephemeris. It is also noted that one of the essential components of location errors in GNSS is the error in the calibration of delays, primarily in the transmitting paths of the navigation spacecraft (NSC). The analysis of the possibility of obtaining high-precision corrections in real time for various GNSS functional additions at the present time is carried out.

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