A digital open-loop Doppler processing prototype for deep-space navigation  

作　　者：JIAN NianChuan SHANG Kun ZHANG SuJun WANG MingYuan SHI Xian PING JingSong YAN JianGuo TANG GeShi LIU JunZe QIU Shi FUNG Lai-Wo ZHANG Hua WANG Zhen GOU Wei 

机构地区：[1]Shanghai Astronomical Observatory of Chinese Academy of Sciences,Shanghai 200030,China [2]Graduate University of Chinese Academy of Sciences,Beijing 100049,China [3]Beijing Aerospace Command and Control Center,Beijing 100094,China [4]Urumqi Astronomical Station of National Astronomical Observatories,CAS,Urumqi 830011,China [5]State Key Laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,Wuhan University,Wuhan 430070,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2009年第12期1849-1857,共9页中国科学：物理学、力学、天文学（英文版）

基　　金：Supported by the Innovation Research Plan of CAS,the National Natural Science Foundation of China (Grant Nos. 10973031 and 40904006);the CAS Key Research Program (Grant No. KJCX2-YW-T13-2), and Beijing Aerospace Command and Control Center

摘　　要：A prototype based on digital radio technology with associated open-loop Doppler signal processing techniques has been developed to measure a spacecraft's line-of-sight velocity. The prototype was tested in China's Chang'E-1 lunar mission relying on S-band telemetry signals transmitted by the sat-ellite,with results showing that the residuals had a RMS value of ～3 mm/s (1σ ) using 1-sec integration,which is consistent with the Chinese conventional USB (Unified S-Band) tracking system. Such preci-sion is mainly limited by the short-term stability of the atomic (e.g. rubidium) clock at the uplink ground station. It can also be improved with proper calibration to remove some effects of the transmission media (such as solar plasma,troposphere and ionosphere),and a longer integration time (e.g. down to 0.56 mm/s at 34 seconds) allowed by the spacecraft dynamics. The tracking accuracy can also be in-creased with differential methods that may effectively remove most of the long-term drifts and some of the short-term uncertainties of the uplink atomic clock,thereby further reducing the residuals to the 1 mm/s level. Our experimental tracking data have been used in orbit determination for Chang'E-1,while other applications (such as the upcoming YH-1 Mars orbiter) based on open-loop Doppler tracking will be initiated in the future. Successful application of the prototype to the Chang'E-1 mission in 2008 is believed to have great significance for China's future deep space exploration.A prototype based on digital radio technology with associated open-loop Doppler signal processing techniques has been developed to measure a spacecraft’s line-of-sight velocity. The prototype was tested in China’s Chang’E-1 lunar mission relying on S-band telemetry signals transmitted by the satellite, with results showing that the residuals had a RMS value of ～3 mm/s (1 σ) using 1-sec integration, which is consistent with the Chinese conventional USB (Unified S-Band) tracking system. Such precision is mainly limited by the short-term stability of the atomic (e.g. rubidium) clock at the uplink ground station. It can also be improved with proper calibration to remove some effects of the transmission media (such as solar plasma, troposphere and ionosphere), and a longer integration time (e.g. down to 0.56 mm/s at 34 seconds) allowed by the spacecraft dynamics. The tracking accuracy can also be increased with differential methods that may effectively remove most of the long-term drifts and some of the short-term uncertainties of the uplink atomic clock, thereby further reducing the residuals to the 1 mm/s level. Our experimental tracking data have been used in orbit determination for Chang’E-1, while other applications (such as the upcoming YH-1 Mars orbiter) based on open-loop Doppler tracking will be initiated in the future. Successful application of the prototype to the Chang’E-1 mission in 2008 is believed to have great significance for China’s future deep space exploration.

关 键 词：OPEN-LOOP DOPPLER DIFFERENTIAL DOPPLER DEEP space NAVIGATION Chang’E-1 

分 类 号：V441[航空宇航科学与技术—飞行器设计]