关键词: 月球导航, GNSS导航, 月球导航增强卫星, 双向时间同步, 钟差解耦, 实时高精度

Abstract: It is of great significance that lunar spacecraft has the ability of GNSS autonomous navigation for the demands of high precision，low cost and autonomous navigation in the following human and unmanned lunar exploration task，which keeps up with the simple and low cost trends of the future lunar mission.However，the direct application of the earth GNSS navigation to the high precision earth-moon navigation scenario has the limited capacity of real-time navigation，which cannot meet the demand of the high precision navigation application for the future lunar exploration mission.Thus，the earth-moon space navigation method based on the GNSS and navigation  augmentation satellite was developed.By adding a moon navigation node which broadcasts navigation signal，the time synchronization link was built between GNSS and moon navigation satellite，and also between lunar users and moon navigation satellite，the clock and position error were decoupled and high precision real-time three-dimensional absolute navigation was realized.At last，the precision of the proposed navigation method was simulated and the results of simulation show that the PDOP of the user was highly improved.The positioning accuracy is better than 50 m and the method has high practicability.

Key words:  , lunar navigation；GNSS-based navigation；lunar navigation augmentation satellite；dualway time synchronization；clock error decoupling；real-time high precision