卡尔曼滤波卫星授时的仿真技术  

Simulation technology for Kalman filtering in satellite time transfer

作　　者：李罡[1] 吕晶[1] 常江[1] 戴卫恒[1] 李广侠[1] 

机构地区：[1]解放军理工大学通信工程学院,江苏南京210007

出　　处：《解放军理工大学学报（自然科学版）》2008年第4期312-316,共5页Journal of PLA University of Science and Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(60702021)

摘　　要：为了提高无线导航卫星系统授时精度,提出了采用卡尔曼滤波对用户时钟钟差、钟漂及老化率进行估计,并预测出下一采样时刻用户时钟与系统时的差值的闭环授时方法,设计了卡尔曼滤波器。分别对单星和多星的授时问题进行了讨论,理论证明了采用多颗卫星授时可提高授时精度,并给出了克拉默罗界。利用STK软件实时产生卫星三维位置和速度,建立了用户时钟仿真模型和观测误差仿真模型,对所提出的方法在单星和多星的情况下进行了仿真。结果表明,在噪声较大情况下仍能保持较高的授时精度。In order to improve the accuracy of time transfer of RNSS（radio navigation satellite system）, a novel closed loop method of Kalman filtering was proposed to estimate the clock offset, clock shifting and clock aging rate, so as to predict the clock bias between user time and system time at the next sampling time, and the design of Kalman filtering was given. Moreover, the situation of single satellite and multiple satellites were both discussed, theoretically proving that the performance of time transfer can be improved by using multiple satellites, and Cramer-Rao bound was presented as well. Finally, the threee-dimension position and velocity of each satellite were generated by STK. User clock model and observation error model were set up to simulate the method in the condition of single satellite and multiple satellites. The result indicates that the accuracy of time transfer can be kept even under heavy noise situation.

关 键 词：卫星授时 卡尔曼滤波 加权 克拉默罗界 

分 类 号：TN967.1[电子电信—信号与信息处理]