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1

An influence of the covariance between single orbit parameters on the accuracy of observations of the pseudo-ranges and phase differences

Skeivalas Jonas, Paršeliūnas Eimuntas, Putrimas Raimundas, Šlikas Dominykas

Metrology and Measurement Systems

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2020

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Vol. 27, nr 1

131--140

EN

The possibilities to improve values of the satellite orbit elements by employing the pseudo-ranges and differences of carrier phase frequencies measured at many reference GPS stations are analysed. An improvement of orbit ephemeris is achieved by solving an equation system of corrections of the pseudo-ranges and phase differences with the least-squares method. Also, equations of space coordinates of satellite orbit points expressed by ephemeris at fixed moments are used. The relation between the accuracy of the pseudo-ranges and phase differences and the accuracy of the satellite ephemeris is analysed. Formulae for estimation of the influence of the ephemeris on the measured pseudo-ranges and phase differences and for prediction of the accuracy of the pseudo-ranges and phase differences were obtained. An influence of the covariance between single orbit parameters on the accuracy of the pseudo-ranges and phase differences is detected.

2

New high-precision values of the geodetic rotation of the major planets, Pluto, the Moon and the Sun

Pashkevich V. V.

Artificial Satellites : Journal of Planetary Geodesy

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2016

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Vol. 51, No. 2

61--73

EN

This investigation is continuation of our studies of the geodetic (relativistic) rotation of the Solar system bodies (Eroshkin and Pashkevich, 2007) and (Eroshkin and Pashkevich, 2009). For each body (the Moon, the Sun, the major planets and Pluto) the files of the values of the components of the angular velocity of the geodetic rotation are constructed over the time span from AD1000 to AD3000 with one day spacing, by using DE422/LE422 ephemeris (Folkner, 2011), with respect to the proper coordinate systems of the bodies (Seidelmann et al., 2005). For the first time in the perturbing terms of the physical librations for the Moon and in Euler angles for other bodies of the Solar system the most essential terms of the geodetic rotation are found by means of the least squares method and spectral analysis methods.

3

RERS2014 and MRS2014: new high-precision rigid Earth rotation and Moon rotation series

Pashkevich V. V.

Artificial Satellites : Journal of Planetary Geodesy

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2015

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Vol. 50, No. 1

35--40

EN

Numerical investigation of the Earth and Moon rotational motion dynamics is carried out at a long time intervals. In our previous studies (Pashkevich, 2013), (Pashkevich and Eroshkin, 2011) the high-precision Rigid Earth Rotation Series (designated RERS2013) and Moon Rotation Series (designated MRS2011) were constructed. RERS2013 are dynamically adequate to the JPL DE422/LE422 (Folkner, 2011) ephemeris over 2000 and 6000 years and include about 4113 periodical terms (without attempt to estimate new subdiurnal and diurnal periodical terms). MRS2011 are dynamically adequate to the JPL DE406/LE406 (Standish, 1998) ephemeris over 418, 2000 and 6000 years and include about 1520 periodical terms. In present research have been improved the Rigid Earth Rotation Series RERS2013 and Moon Rotation Series MRS2011, and as a result have been constructed the new high-precision Rigid Earth Rotation Series RERS2014 and Moon Rotation Series MRS2014 dynamically adequate to the JPL DE422/LE422 ephemeris over 2000 and 6000 years, respectively. The elaboration of RERS2013 is carried out by means recalculation of sub-diurnal and diurnal periodical terms. The residuals in Euler angles between the numerical solution and RERS2014 do not surpass 3 μas over 2000 years. Improve the accuracy of the series MRS2011 is obtained by using the JPL DE422/LE422 ephemeris. The residuals in the perturbing terms of the physical librations between the numerical solution and MRS2014 do not surpass 8 arc seconds over 6000 years.

4

RERS2013: a new high-precision rigid Earth rotation series

Pashkevich V. V.

Artificial Satellites : Journal of Planetary Geodesy

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2014

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Vol. 49, No. 3

161--177

EN

In the previous investigation (Pashkevich, 2013) the high-precision Rigid Earth Rotation Series (designated RERS2012) dynamically adequate to the JPL DE406/LE406 (Standish, 1998) ephemeris over 2000 and 6000 years were constructed. The main aim of present research is improvement of the Rigid Earth Rotation Series RERS2012 by using the JPL DE422/LE422 (Folkner, 2011) ephemeris, and as a result is produced construction of the new high-precision Rigid Earth Rotation Series dynamically adequate to the JPL DE422/LE422 ephemeris over 2000 and 6000 years. The discrepancies in Euler angles between the high-precision numerical solutions and the semi-analytical solutions of the rigid Earth rotation problem are investigated by least squares and spectral analysis methods using the iterative algorithm (Pashkevich, 2013). In order to demonstrate the good convergence of this iterative algorithm are constructed additional solutions of the rigid Earth rotation dynamically adequate to the JPL DE422/LE422 over 2000 years by improvement solutions SMART97 (Bretagnon et al., 1998) and S9000 (Pashkevich and Eroshkin, 2005a). As the results of this investigation, the new improved high-precision Rigid Earth Rotation Series RERS2013 dynamically adequate to the DE422/LE422 ephemeris over 2000 and 6000 years have been constructed. The discrepancies in Euler angles between the numerical solution and RERS2013 do not surpass: 4 as over 2000 years, 1 mas over 6000 years. The RERS2013 series is more accurate than the RERS2012 series, which is dynamically adequate to the DE406/LE406 ephemeris. The good convergence of the iterative algorithm of this study has been confirmed.

5

Construction of the numerical and semi-analytical solutions of the rigid Earth rotation at a long time intervals

Pashkevich V. V.

Artificial Satellites : Journal of Planetary Geodesy

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2013

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Vol. 48, No. 1

25--37

EN

This research is the continuation of our studies of the rigid Earth rotation at a long time intervals (Pashkevich V.V. and Eroshkin G.I., 2005). The main purpose of this investigation is the construction of the new high-precision Rigid Earth Rotation Series 2012 (RERS2012), dynamically adequate to the JPL DE406/LE406 ephemeris (Standish E. M., 1998). The dynamics of the rotational motion of the rigid Earth is studied numerically by using Rodrigues-Hamilton parameters over 2000 and 6000 years. The numerical solution of the rigid Earth rotation is implemented with the quadruple precision of the calculations. The orbital motions of the disturbing celestial bodies are defined by the DE406/LE406 ephemeris. The initial conditions of the numerical integration are taken from SMART97 (Bretagnon P. et al., 1998) and S9000 (Pashkevich V.V. and Eroshkin G.I. 2005). The results of the numerical solutions of the problem are compared with the semi-analytical solutions of the rigid Earth rotation (SMART97 and S9000, respectively) with respect to the fixed ecliptic of epoch J2000. The investigation of these discrepancies is carried out by the least squares and spectral analysis methods for the relativistic (Kinematical) case, in which the geodetic perturbations (the most essential relativistic perturbations) in the Earth rotation are taken into account. As a result, the Rigid Earth Rotation Series (RERS2012) is constructed, which is dynamically adequate to the DE406/LE406 ephemeris over 2000 and 6000 years. The discrepancies between the new numerical solutions and the semi-analytical solutions of MRS2012 do not surpass 12 μas over 2000 year time interval and 2 mas over 6000 year time interval. Thus, the result of the comparison demonstrates a good consistency of RERS2012 series with the DE406/LE406 ephemeris.

6

Construction of the new high-precision Moon rotation series at a long time intervals

Pashkevich V. V., Eroshkin G. I.

Artificial Satellites : Journal of Planetary Geodesy

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2011

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Vol. 46, No. 2

63--73

EN

The main purposes of this research are the construction of the new highprecision Moon Rotation Series (MRS2011), dynamically adequate to the DE404/LE404 and the DE406/LE406 ephemeris, over long time intervals. The comparison of the new highprecision Moon Rotation solutions of MRS2011 with the solution of MRS2010 (Pashkevich and Eroshkin, 2010), which is dynamically adequate to the DE200/LE200 ephemeris over 418.9 year time interval, is performed. The dynamics of the rotational motion of the Moon is studied numerically by using Rodrigues-Hamilton parameters over 418.9, 2000 and 6000 years. The numerical solution of the Moon rotation is implemented with the quadruple precision of the calculations. The results of the numerical solution of the problem are compared with the composite semi-analytical theory of the Moon rotation (SMR) (Pashkevich and Eroshkin, 2010) with respect to the fixed ecliptic of epoch J2000. The initial conditions of the numerical integration are taken from SMR. The investigation of the discrepancies is carried out by the least squares and spectral analysis methods for the Newtonian case. All the secular, periodic and Poisson terms, representing the behavior of the residuals, are interpreted as corrections to SMR semi-analytical theory. As a result, the Moon Rotation Series (MRS2011) is constructed, which is dynamically adequate to the DE404/LE404 and the DE406/LE406 ephemeris over 418.9, 2000 and 6000 years. A numerical solution for the Moon rotation is obtained anew with the new initial conditions calculated by means of MRS2011. The discrepancies between the new numerical solution and the semi-analytical solution of MRS2011 do not surpass 20 mas over 418.9 year time interval, 64 mas over 2000 year time interval and 8 arc seconds over 6000 year time interval. Thus, the result of the comparison demonstrates a good consistency of MRS2011 series with the DE/LE ephemeris.

7

Application of the spectral analysis for modeling the rotations of the Moon

Pashkevich V. V., Eroshkin G. I.

Artificial Satellites : Journal of Planetary Geodesy

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2010

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Vol. 45, No. 4

153--162

EN

The main purposes of this research are the development of the optimal spectral analysis schemes for the investigation of the rotational motion of the Moon and then the comparison between the result of the optimal spectral analysis of the rotational motions of the Earth and the Moon. Dynamics of the rotational motion of the Moon is studied numerically by using Rodrigues-Hamilton parameters over 418.9 year time interval. The results of the numerical solution of the problem are compared with the composite semi-analytical theory of the Moon rotation (SMR) represented by Cassini relations and the semi-analytical solutions of the lunar physical libration problem (Eckhardt, 1981), (Moons, 1982), (Moons, 1984), (Pešek, 1982). The initial conditions of the numerical integration are taken from SMR. The investigation of the discrepancies is carried out by the optimal spectral analysis methods for the Newtonian case. All the periodic terms representing the behavior of the residuals are interpreted as corrections to SMR semi-analytical theory. As a result, the Moon Rotation Series (MRS2010) is constructed, which is dynamically adequate to the DE200/LE200 ephemeris over 418.9 year time interval. A numerical solution for the Moon rotation is obtained anew with the new initial conditions calculated by means of MRS2010. The discrepancies between the new numerical solution and MRS2010 do not surpass 20 mas over 418.9 year time interval. The result of the comparison demonstrates that MRS2010 series represent more accurately the Moon rotation than SMR series.

8

Depesza nawigacyjna systemów satelitarnych obecnie i w przyszłości

Januszewski J.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2009

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nr 9

1938-1944

PL

W artykule scharakteryzowano różne depesze nawigacyjne emitowane przez satelity systemów GPS i GLONASS oraz satelity geostacjonarne systemów wspomagających (SBAS). Opisano również wiadomości emitowane przez brzegowe stacje odmiany różnicowej NSS oraz przewidywaną strukturę depeszy przyszłego systemu Galileo.

EN

The different navigation data messages transmitted by GPS satellites, GLONASS satellites and Satellite Based Augmentation System (SBAS) geostationary satellites are described in the paper. Additionally the message transmitted by differential SNS reference station and the planned navigation message structure of the future Galileo system are presented.

9

On the geodetic rotation of the major planets, the Moon and the Sun

Eroshkin G. I., Pashkevich V. V.

Artificial Satellites : Journal of Planetary Geodesy

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2009

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Vol. 44, No. 2

43--52

EN

The problem of the geodetic (relativistic) rotation of the major planets, the Moon and the Sun was studied in the paper by Eroshkin and Pashkevich (2007) only for the components of the angular velocity vectors of the geodetic rotation, which are orthogonal to the plane of the fixed ecliptic J2000. This research represents an extension of the previous investigation to all the other components of the angular velocity vector of the geodetic rotation, with respect to the body-centric reference frame from Seidelmann et al. (2005).

10

Geodetic rotation of the solar system bodies

Eroshkin G. I., Pashkevich V. V.

Artificial Satellites : Journal of Planetary Geodesy

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2007

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Vol. 42, No. 1

59--70

EN

The problem of the geodetic (relativistic) rotation of the major planets, the Moon, and the Sun is studied by using DE404/LE404 ephemeris. For each body the files of the ecliptical components of the vectors of the angular velocity of the geodetic rotation are determined over the time span from AD1000 to AD3000 with one day spacing. The most essential terms of the geodetic rotation are found by means of the least squares method and spectral analysis methods.

11

Construction of the non-rigid Earth rotation series

Pashkevich V. V.

Artificial Satellites : Journal of Planetary Geodesy

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2007

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Vol. 42, No. 4

215--227

EN

Last years a lot of attempts to derive a high-precision theory of the non-rigid Earth rotation are carried out. For these purposes different transfer functions are used. Usually these transfer functions are applied to the series representing the nutation in the longitude and the obliquity of the rigid Earth rotation with respect to the ecliptic of date. The aim of this investigation is a construction of new high-precision non-rigid Earth rotation series (SN9000), dynamically adequate to the DE404/LE404 ephemeris over 2000 time span years, which are presented as functions of the Euler angles ψ, θ and φ with respect to the fixed ecliptic plane and equinox J2000.0.