基于BD导航卫星的空基伪卫星网络动态共视授时技术

Dynamic Common-View Time Service of Wide Area Air-Borne Pseudo-Satellite Network Based on BD Navigation Satellite

为实现广域空基伪卫星网络的精确共视授时,提出了网内传递共视授时方法;为进一步削弱对流层延迟误差的影响,提出了卫星共视选星策略;通过分析SIN/BD组合导航系统定位误差的统计特性,在揭示授时误差与组合导航系统定位误差之间数学关系的基础上,又提出采用整网平均法用以减少动态平台定位误差的影响。仿真结果表明:传递共视方法能很好地完成大区域网络的授时,有选星策略比无选星策略的对流层延迟减少约80%,运用整网平均的方法能实现优于0.3 ns的高精度共视授时,所提方法能够大幅度提高动态共视授时的精度。

To achieve high precision time service of wide area pseudo-satellite network, this article proposed the method of transmission common-view time service inside the network, analyzed the errors of the process of common-view time service, put forward the method of satellite common-view selection in order to further reduced the effect of troposphere delay, after that analyzed the distribution of position error of the SIN/BD integrated navigation system, then raised the net average to eliminate the effect of position error, improved the precision of time service of pseudo-satellite network significantly. Simulation result showed that the method of transmission common-view can do a good job to finish the large-scale network time service; common-view selection reduced almost 80% of troposphere delay than none;and net average can achieve the service precision of common-view time less than 0.3 ns, the method that this article proposed can improve the precision of dynamic time service of pseudo-satellite network significantly.