gyroscopyГироскопия и навигацияGiroskopiya i Navigatsiya0869-70352075-0927AO «Концерн «ЦНИИ «Электроприбор»10.17285/0869-7035.0097gyroscopy-130Research ArticleСтатьиКоррекция шкалы времени спутников IRNSS/NavICSatellite Time Keeping Methodology for IRNSS/NavIC Constellationhttps://orcid.org/0000-0003-1648-9587РаджаяК.RajaiahK.

Кайтха Раджая, научный сотрудник

560017; Бангалор

560017; Bangalore

МанамоханК.ManamohanK.

Камат Манамохан, научный сотрудник

560017; Бангалор

560017; Bangalore

НирмалаС.NirmalaS.

Срини Нирмала, научный сотрудник

560017; Бангалор

560017; Bangalore

https://orcid.org/0000-0003-4978-7011ВенкатаппаР. Т.VenkatappaR. T.

Рао Туму Венкатаппа, профессор

физический факультет

506004; Телангана

Department of Physics

506004; Telangana

https://orcid.org/0000-0001-7688-8825ПрашантхЧ. У.PrashanthC. U.

Ч. Упадхья Прашантх, доктор наук, научный сотрудник

лаборатория электрооптических систем

560058; Бангалор

Laboratory for Electro-Optics Systems

560058; Bangalore

Спутниковый центр им. Рао, Индийская организация космических исследованийИндияU.R. Rao Satellite Centre, Indian Space Research OrganisationIndiaНациональный технологический институт ВарангалаИндияNational Institute of Technology WarangaIndiaИндийская организация космических исследованийИндияIndian Space Research OrganisationIndia2022210520253033140Copyright © Раджая К., Манамохан К., Нирмала С., Венкатаппа Р.Т., Прашантх Ч.У., 20252025Раджая К., Манамохан К., Нирмала С., Венкатаппа Р.Т., Прашантх Ч.У.Rajaiah K., Manamohan K., Nirmala S., Venkatappa R.T., Prashanth C.U.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://www.gyroscopy.ru/jour/article/view/130

   Точность дальномерных измерений, выполняемых при помощи навигационных спутников, зависит главным образом от поправок бортовых часов, которые периодически транслируются пользователям. В течение срока службы спутника смещение бортовых часов относительно системного времени – важнейший параметр, накапливающийся вследствие сдвига и дрейфа частоты, – должно находиться в заданном интервале. В спутниках Индийской региональной навигационной спутниковой системы (IRNSS) смещение часов удерживается в допустимом интервале путем ввода поправок к частоте бортового генератора. В данной статье обсуждается метод вычисления смещения часов по беззапросным дальномерным измерениям. Описывается применяемый в спутниках IRNSS способ синхронизации, который позволяет удерживать смещение спутниковых часов в допустимом интервале максимальное время.

   Accuracy of range measurements using navigation satellites primarily depends on on-board clock correction parameters which are broadcasted to users periodically. The on-board clock offset, a critical correction parameter which accumulates due to fractional frequency offset as well as frequency drift, has to be maintained within the allocated broadcast limit throughout the satellite’s service. In IRNSS satellites, the clock offset is maintained within the broadcast limit by applying frequency offset corrections to the on-board atomic clock monitoring unit. In this paper, we discuss the methodology implemented for computing the clock offset using one-way range measurement data. Further, we report the time keeping methodology employed in IRNSS satellites that enables maintaining the satellite clock offset within the broadcast limit with minimum number of intervening frequency offset corrections throughout their operational life time.

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The authors declare that there are no conflicts of interest present.