一种改进的平方根滤波在卫星钟差实时解算中的应用  

An Improved Method of Square Root Filter and Its Application in Real-Time Satellite Clock Offset Determination

作　　者：代桃高 李建文[1,2] 赵静 郭亮亮[1,2] 

机构地区：[1]信息工程大学导航与空天目标工程学院,郑州市科学大道62号450001 [2]北斗导航应用技术河南省协同创新中心,郑州市科学大道62号450001 [3]成都信息工程大学大气探测重点实验室,成都市学府路一段24号610225

出　　处：《大地测量与地球动力学》2017年第9期946-950,共5页Journal of Geodesy and Geodynamics

摘　　要：目前普遍采用卡尔曼滤波方法来实现非差法卫星钟差的实时解算。平方根滤波可以增强数值计算的稳定性,避免滤波发散,但矩阵的求逆会耗费较长的计算时间;序贯算法可以避免对矩阵直接求逆,能提升计算效率。综合两种算法的优点,提出一种基于序贯算法的平方根滤波器,并应用于卫星钟差的实时解算,得到的卫星钟差精度优于0.2ns,且计算时长缩短40%。Currently, the Kalman filter is widely used to calculate satellite clock offset in real-time based on the un-differenced method. Square root filter can enhance the stability of numerical calcula- tion, and avoiding filtering divergence, but the inversion computation time of matrix will take longer. The sequential algorithm can improve computational efficiency for avoiding direct matrix inversion. Taking the advantages of these two algorithms, a new square root filter method is proposed based on the sequential algorithm; it is then applied to satellite clock offset calculating in real-time. The result shows that the accuracy of satellite clock offset is better than 0.2 ns, and the calculation time is re duced by 40%.

关 键 词：平方根滤波 序贯算法 滤波发散 卫星钟差 非差法 

分 类 号：P228[天文地球—大地测量学与测量工程]