文档介绍：A Method pensating Navigation Clock Frequency Drift Based On DDS He dong1, Zhao ming 2, Xie jun3, Qu yongsheng4, Sun yunfeng51. China Academy of Space Technology (Xi’an), CAST(Xi’an), Xi’an, China Academy of Space Technology (Xi’an), CAST(Xi’an), Xi’an, China 3. China Academy of Space Technology, Beijing, China @, 2. 1900xyz@ Abstract: Insatellite navigation and positioning system,high-level stability time & frequency signalis determined by high precision atomic clocks. However, the frequency of satellite clock will e uracy due to its frequency drift, which will affect the satellite positioning and timing performance. Based on the analysis of on-board atomic clocks frequency characteristics, a method pensating the frequency drift is proposedapplying DDS technology. Our method controls the frequency adjusting cycle time to realize frequency drift correcting. The satellite clock frequency accuracy can be corrected automatically, smoothly and constantly. Therefore, the frequency jump by direct change to the satellite clock frequency can be avoided. Meanwhile we developed hardware circuit and software for the engineering model and studied the testing method. A rubidium atomic clock was tested in this method. The result shows this method can realize accurate correction of the frequency drift. The frequency drift can be reduced more than a words