Коррекция шкалы времени спутников IRNSS/NavIC

   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.

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