【作者】 郭美军； 朱翔宇； 贾小林； 郑洁； 孙广； 刘晓刚； 肖云； 李双钦；

【Author】 Meijun GUO;Xiangyu ZHU;Xiaolin JIA;Jie ZHENG;Guang SUN;Xiaogang LIU;Yun XIAO;Shuangqin LI;Xi’an aerors data technology Co.Ltd;Xi’an Research Institute of Surveying and Mapping;

【机构】 西安航天天绘数据技术有限公司； 西安测绘研究所；

【摘要】 BDS区域导航系统最早发射的卫星已有7年,需要对卫星钟健康状态各项指标进行长期分析,以获取卫星钟寿命是否已到末期。采用武汉大学分析中心近两年的精密钟差数据,采用中位数法对数据进行了预处理,采用二次多项式拟合模型对卫星钟差进行了拟合,分析了星载钟的相位、频率、频漂指标的物理特性以及相位拟合残差、残差标准差卫星钟噪声特性。利用重叠哈德玛方差分析了卫星钟差的频率稳定性。通过实际数据计算全面分析和评估了BDS卫星钟的长期特性。得出结论:BDS GEO卫星钟存在频繁的跳频、跳相;BDS卫星钟的频漂基本在e-18量级;BDS MEO卫星钟的相位残差在1ns内,残差标准差优于0.5ns,GEO和IGSO卫星钟的相位残差在2ns内,残差标准差优于1ns;所有卫星钟的万秒频率稳定度维持在e-14量级;卫星钟噪声与频率稳定度有一定的线性关系,而与卫星钟本身的物理特性没有直接关联。更多还原

【Abstract】 The earliest satellite has launched for 7 years on Bei Dou Regional Navigation System.To get the Satellite clock life is to the end, It is necessary to analysis the long-term health indicators of Satellite clock. Precise satellite clock data products of Wu Han University Analysis Center are used to conduct the performance analysis of BDS satellite clocks.The Satellite clock data are preprocessed by using median absolute deviation(MAD).Long-term variations of satellite clocks’ phase,frequency,frequency drift,Phase fitting residuals,Standard deviation of residuals are analyzed based on the quadratic polynomial model.Frequency stability of BDS satellite clocks is calculated based on Overlapping Hadamard Variance.Based on above mentioned discussions and corresponding experiment results,the long-term performance of BDS satellite clocks is relatively comprehensively evaluated and analyzed.In addition,some valuable conclusions are obtained.There are lots of frequency hopping and phase jumping of GEO satellite clocks.The frequency drift of BDS satellite clocks are about e-18.The Phase fitting residuals within 1 ns and Standard deviation of residuals is better than 0.5 ns for BDS MEO satellite clocks, the Phase fitting residuals within 2 ns and Standard deviation of residuals is better than 1 ns for BDS GEO and IGSO satellite clocks.The frequency stabilities of all satellite clocks in ten-thousand seconds is about e-14.There is a certain linear relationship between satellite clock noise and frequency stabilities,but no drect correlation with the satellite’s physical characteristics.更多还原