Low-latitude ionospheric behavior directly interferes with a wide range of applications dependent on signals and information from satellites. The most severe and variable events are plasma bubbles and ionospheric scintillation. During plasma bubble events, large and steep plasma density gradients may intersect transionospheric signal from satellites, especially around the equatorial anomaly region. Large ionospheric spatial gradients (or decorrelations) are a critical component of ionospheric threat models for global navigation satellite systems augmentation systems; however, the models cannot assimilate abrupt changes in ionospheric behavior. In this article, an investigation of the relationship between plasma depletions, the occurrence of scintillation, and strong ionospheric spatial decorrelation events was conducted. The results indicate that strong scintillations occur when large gradients are verified. Additionally, the most critical ionospheric spatial gradients were verified mostly under certain conditions: when satellite signals are aligned with the plasma bubble propagation along geomagnetic field lines. Therefore, even though amplitude scintillation may degrade communications, the critical gradient events seem to be related to a particular configuration of satellite signal across the ionosphere. Thus, it is recommended that ionospheric threat models for augmentation systems in low-latitude regions consider this alignment aspect.

中文翻译：

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由与赤道等离子体气泡对齐的信号传播路径引起的强电离层空间梯度事件

低纬度电离层行为直接干扰依赖于来自卫星的信号和信息的广泛应用。最严重和多变的事件是等离子体气泡和电离层闪烁。在等离子体气泡事件期间，大而陡峭的等离子体密度梯度可能与来自卫星的跨电离层信号相交，特别是在赤道异常区域周围。大电离层空间梯度（或去相关）是全球导航卫星系统增强系统的电离层威胁模型的关键组成部分；然而，这些模型无法同化电离层行为的突然变化。在本文中，对等离子体耗尽、闪烁的发生和强电离层空间去相关事件之间的关系进行了调查。结果表明，当验证大梯度时会发生强闪烁。此外，最关键的电离层空间梯度主要在某些条件下得到验证：当卫星信号与沿地磁场线的等离子体气泡传播对齐时。因此，尽管幅度闪烁可能会降低通信性能，但临界梯度事件似乎与电离层中卫星信号的特定配置有关。因此，建议低纬度地区增强系统的电离层威胁模型考虑这种对齐方面。当卫星信号与沿地磁场线的等离子体气泡传播对齐时。因此，尽管幅度闪烁可能会降低通信性能，但临界梯度事件似乎与电离层中卫星信号的特定配置有关。因此，建议低纬度地区增强系统的电离层威胁模型考虑这种对齐方面。当卫星信号与沿地磁场线的等离子体气泡传播对齐时。因此，尽管幅度闪烁可能会降低通信性能，但临界梯度事件似乎与电离层中卫星信号的特定配置有关。因此，建议低纬度地区增强系统的电离层威胁模型考虑这种对齐方面。