对于LEO卫星振荡器的多约束协同优化LQG频率定向方法
Dongdong Wang1,2, Wenhe Liao1, Bin Liu2
1School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
Sensors (Basel, Switzerland)
|August 14, 2025
概括
这项研究介绍了低地球轨道 (LEO) 卫星中烤箱控制晶振荡器 (OCXOs) 的精确转向方法. 该方法显著提高了钟表精度和频率稳定性,用于厘米级定位.
科学领域:
- 航空航天工程 航空航天工程
- 控制系统 控制系统
- 信号处理 信号处理
背景情况:
- 高精度的时频系统对于低地球轨道 (LEO) 卫星的实时厘米级定位至关重要.
- 在LEO卫星中使用的烤箱控制晶振荡器 (OCXOs) 存在长期稳定性问题,由于时钟错误的积累,降低了定位精度.
- 现有系统面临着在尺寸,功率和成本限制下平衡时钟偏差精度,频率稳定性和相连续性的挑战.
研究的目的:
- 开发一种新的频率精度定向方法,用于LEO卫星中的OCXO.
- 改善OCXO的时间频率性能,解决传统时钟源的局限性.
- 为LEO卫星导航提供低成本,高精度的定时频率参考解决方案.
主要方法:
- 提出了一种线性二次高斯式 (LQG) 频率精度转向方法,整合了四维约束集成 (FDCI) 模型和层次重量优化.
- 改进了一个改进的系统错误模型来量化LQG闭环控制系统的协差元件 (Σ11, Σ22).
- 使用优先驱动的协作优化机制与FDCI模型系统地确定权重矩阵,在性能标准之间进行强大的权衡.
主要成果:
- 减少时钟误差 根平均平方 (RMS) 到 0.14 ns,比传统的 PID 控制有 37% 的改进.
- 实现了多次尺度的频率稳定性增强:9.38 × 10^-13在100秒和4.22 × 10^-14在10,000秒 (比自由运行的OCXO大小的三倍).
- 与纯卡尔曼过相比,稳定性得到了93%的改进,并且对短期稳定性而言,量子化噪声的影响在13%以内.
结论:
- 拟议的LQG频率精确转向方法有效地提高了OCXO时间频率性能,用于LEO卫星应用.
- 理论约束和性能优化的系统集成为平衡多维要求提供了强大的解决方案.
- 这种方法提供了具有成本效益的,高精度的定时频率参考,对于先进的LEO卫星导航服务至关重要.
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