光学学报, 2018, 38 (9): 0901001, 网络出版: 2019-05-09
大气折射对双波长空间激光授时偏差的影响 下载: 875次
Influence of Atmospheric Refraction on Timing Deviation of Time Transfer by Space Laser Link at Double Wavelengths
大气光学 空间激光授时 大气折射率 不对称时延差 位置偏差 atmospheric optics time transfer by space laser link atmospheric refractive index asymmetric delay deviation position deviation
摘要
针对双波长空间激光授时系统受大气折射率分布的影响而产生授时偏差的问题,利用实测气象数据建立了大气折射率分布对授时偏差的影响模型。以该模型为基础分别仿真研究了在地面终端捕获模式和星上终端捕获模式下双向链路不对称时延差和收发终端位置偏差随不同地区、不同月份和不同天顶角的变化规律。结果表明:大气压强越低,大气温度越高,不对称时延差和收发终端位置偏差越小;星上终端捕获模式下的授时偏差达到百皮秒量级;地面终端捕获模式下的授时偏差达到纳秒量级,通过进一步双向精密对准可将其减少到十皮秒量级。在卫星过顶时间内,不对称时延差和收发终端位置偏差随天顶角的变化而变化,并且存在地面终端地理位置的差异,需实时校正并消除不对称时延差和收发终端位置偏差。
Abstract
In order to evaluate the impact of atmospheric refractive index distribution on timing deviation of time transfer by space laser link at double wavelengths, we propose the model of atmospheric refractive index distribution influenced on timing deviation with the measured meteorological data. The asymmetric delay deviation and the position deviation of the transceiver terminal are simulated respectively in different regions, different months and different zenith angles based on the ground terminal capturing mode and the satellite terminal capturing mode. The results show that the asymmetric delay deviation and the position deviation are smaller when the atmospheric pressure is lower and the atmospheric temperature is higher. The timing deviation of satellite terminal capturing mode is hundreds of picoseconds. The timing deviation of the ground terminal capturing mode reaches to nanoseconds, which can be decreased to about ten picoseconds by further bidirectional precision alignment. In the satellite passing time, the asymmetric delay deviation and position deviation change with the variation of the zenith angle, and there are geographical location differences between the ground terminals. In general, it is necessary to correct the asymmetric delay deviation and the position deviation of transceiver terminals in real time.
刘航, 卢麟, 朱勇, 吴传信, 张宝富. 大气折射对双波长空间激光授时偏差的影响[J]. 光学学报, 2018, 38(9): 0901001. Hang Liu, Lin Lu, Yong Zhu, Chuanxin Wu, Baofu Zhang. Influence of Atmospheric Refraction on Timing Deviation of Time Transfer by Space Laser Link at Double Wavelengths[J]. Acta Optica Sinica, 2018, 38(9): 0901001.