【摘要】 随着第25个太阳活动周期的顶峰临近，强磁暴事件频繁发生，并伴随剧烈的辐射带粒子沉降，这些变化显著影响电离层电子密度，进而影响电波传播及通信导航质量.本文基于2022至2023年间18次中等及以上强度的磁暴事件，利用南极长城站接收到的来自NAA、NML、NLK和NPM四个甚低频(VLF)发射台站的信号，分析了磁暴期间VLF信号的变化特征和规律.结果显示，磁暴引起的信号扰动主要发生在日落和夜间，且VLF信号响应明显滞后于Dst指数.信号幅度变化最大值与Dst指数最小值之间的平均时间间隔为5.04 h.信号幅度变化与磁暴强度之间的相关性较弱，夜侧路径的幅度变化均值为5.30 dB，日侧路径为3.23 dB，日落时的幅度变化为6.04 dB.扰动的持续时间均值为1.55 h，与磁暴强度关系不大.磁暴引起的VLF信号扰动与辐射带高能粒子的漂移损失过程密切相关，信号变化程度与电离层D层的初始电子密度状况有关.研究结果揭示了磁暴期间VLF信号的变化特征及其与辐射带粒子沉降过程之间的关联，为未来基于VLF信号的电离层扰动监测和通信系统的影响评估提供了重要的参考依据.更多还原

【Abstract】 As the peak of the 25 th solar cycle approaches, strong geomagnetic storm events are becoming more frequent, often accompanied by intense radiation belt particle precipitation. These changes significantly impact ionospheric electron density, affecting radio wave propagation and the quality of communication and navigation.Based on 18 moderate or stronger geomagnetic storm events that occurred between 2022 and 2023, this study analyzes the variation characteristics and patterns of Very Low Frequency(VLF) signals during these storms using data received at the Great Wall Station(GWS) in Antarctica from 4 VLF transmission stations: NAA,NML, NLK, and NPM. The results show that signal disturbances caused by geomagnetic storms mainly occur during sunset and nighttime, with the VLF signal response significantly delayed relative to the Dst index. The average time interval between the maximum signal amplitude change and the minimum Dst value is approximately 5.04 h. The correlation between signal amplitude changes and storm intensity is weak, with the average amplitude change of the nighttime paths being 5.30 dB, 3.23 dB for daytime paths, and 6.04 dB during sunset. The average disturbance duration is 1.55 h and shows little correlation with storm intensity. The VLF signal disturbances caused by geomagnetic storms are closely related to the drift-loss process of radiation belt high-energy particles. The degree of signal variation is influenced by the initial electron density of the ionospheric D layer. The results provide valuable insights into the VLF signal variation characteristics during geomagnetic storms and their relationship with radiation belt particle precipitation, offering a crucial reference for future ionospheric disturbance monitoring and the evaluation of communication system impacts based on VLF signals.更多还原