Autonomous navigation method and technology implementation of high-precision solar spectral velocity measurement

The velocity information of spacecraft can be directly obtained by the autonomous navigation method based on astronomical spectral velocity measurement. It provides complete direct velocity measurement information for the traditional navigation methods represented by astronomical angle measurement and astronomical ranging, which is of great significance for spacecraft high precision autonomous navigation. This paper comprehensively introduces the principle and navigation method of astronomical spectral velocity measurement, as well as the technical realization of the solar atomic frequency discriminator for autonomous navigation (SAFDAN) based on atomic frequency discrimination velocity measurement. The new SAFDAN is the first instrument to measure the Doppler velocity of spacecraft relative to the Sun. Carried by the CHASE mission, the in-orbit experiment of the SAFDAN is realized, and the in-orbit velocity measurement accuracy reaches 1.93 m/s, which effectively verifies the feasibility of the astronomical spectral velocity measurement method and technology.