改进双向卫星时间和频率传输,使用冗余链接为UTC生成
Zhiheng Jiang1, Victor Zhang2, Thomas E Parker2
1BIPM, Bureau International des Poids et Mesures, Sévres, France.
Metrologia
|April 15, 2024
概括
使用软件定义无线电 (SDR) 接收器的双向卫星时间和频率传输 (TWSTFT) 显著减少了白天变化. 使用冗余的SDR TWSTFT链接进一步提高了时间传输稳定性和协调宇宙时间 (UTC) 计算的稳定性.
科学领域:
- 计量学和时间计时
- 卫星地质测量 卫星地质测
- 信号处理 信号处理
背景情况:
- 双向卫星时间和频率传输 (TWSTFT) 对于生成协调宇宙时间 (UTC) 至关重要.
- 传统的SAtellite时间和测距设备 (SATRE) 调制解调器在TWSTFT中受到每日 (日间) 变化的影响,影响UTC精度.
- 现有的方法,如将TWSTFT与GPS载波相精确点定位 (GPSPPP) 结合起来,可以减轻白天效应,但依赖于GPS.
研究的目的:
- 调查软件定义无线电 (SDR) 接收器在减少TWSTFT.24小时变化的有效性.
- 分析冗余和间接SDR TWSTFT链接的使用,以提高时间传输稳定性和UTC计算.
- 探索一个纯粹的TWSTFT解决方案,独立于GPS,以提高UTC稳定性.
主要方法:
- 在TWSTFT操作中实施SDR接收器,以减少白天变化.
- 分析冗余的SDR TWSTFT链接和间接的TWSTFT链接,以提高稳定性.
- 将SDR TWSTFT结果与GPSPPP结合起来,并评估纯TWSTFT解决方案.
主要成果:
- SDR TWSTFT 降低了大陆链路的日间变化两到三倍,并改善了短期稳定性.
- 使用冗余的SDR TWSTFT链接进一步提高了UTC TWSTFT链接的稳定性.
- 间接 SDR TWSTFT 链接提供纯 TWSTFT 解决方案,通过减少对 GPS 的依赖来提高 UTC 计算的稳定性.
结论:
- SDR TWSTFT是减轻卫星时间传输中日间变化的重大进步.
- 战略性使用冗余和间接的SDR TWSTFT链接为UTC实现提供了更稳定和更强大的方法.
- 使用SDR技术的纯TWSTFT解决方案增强了全球时间尺度计算的独立性和可靠性.
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