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利略和 BeiDou AltBOC信号及其对电离层TEC研究的前景
Chuanfu Chen1, Ilya Pavlov1,2,3, Artem Padokhin1,2,3
1Faculty of Physics, Lomonosov Moscow State University, 119991 Moscow, Russia.
Sensors (Basel, Switzerland)
|October 16, 2024
概括
来自利略和北斗卫星的新超宽带信号显著改善了电离层总电子含量 (TEC) 监测. 这些AltBOC信号提供可靠的单频垂直TEC (vTEC) 估计,即使在太阳能无线电爆发期间.
科学领域:
- 地质物理学和太空物理学 空间物理学
- 卫星导航系统 卫星导航系统
- 大气科学 大气科学
背景情况:
- 传统的全球导航卫星系统 (GNSS) 代码测量对电离层总电子含量 (TEC) 研究来说太杂了.
- 在TEC估计中,超宽带 (UWB) 信号,特别是AltBOC,有可能克服传统BPSK/QPSK信号的局限性.
- 离子层监测对于了解太空天气和确保可靠的GNSS运行至关重要.
研究的目的:
- 为了评估利略E5和 BeiDou B2 AltBOC信号的性能,用于TEC估计.
- 为了比较单频AltBOC相位码组合与双频遗留相位组合的噪声水平.
- 评估射频干扰对AltBOC信号质量的影响及其对电离层监测的影响.
主要方法:
- 分析使用ACRG接收器进行为期两周的高频率GNSS测量.
- 计算TEC根平均平方 (RMS) 值作为不同卫星升高角度间噪声的代理值.
- 在未受干扰和干扰条件下,AltBOC和传统信号之间的信号噪声比率 (SNR) 的比较.
主要成果:
- 单频AltBOC相位码组合的TEC噪声水平与双频遗留相位组合相似.
- 单频BPSK/QPSK TEC噪声明显高于AltBOC信号的噪声.
- 即使在太阳能无线电爆发事件中,AltBOC信号也保持了比BPSK/QPSK信号更高的SNR,防止锁定损失.
结论:
- 利略和 BeiDou AltBOC 信号适用于可靠的单频垂直 TEC (vTEC) 估计.
- 改进的AltBOC信号性能提高了高精度电离层监测的潜力.
- 现在有足够多的北斗和利略卫星传输AltBOC信号,使强大的电离层研究成为可能.
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