地震等自然灾害的爆发通常会引发电离层的扰动。基于GNSS-VTEC技术分析同震电离层异常的扰动特征及其变化规律，探索其背后的发生机理，对地震监测具有重大的科学意义。 论文利用地基GNSS数据研究了南北半球的新西兰和尼泊尔地震电离层扰动特征及变化规律，深入分析了两者的共性特征，并通过南半球的智利地震进行验证。研究的主要内容和成果如下： （1）利用双频载波相位观测值获取各地震发生期间的VTEC，并对扰动变化进行分析，针对电离层扰动趋势项干扰，采用4阶2-8MHz带通滤波方法对其进行去除。最后利用多种扰动特征分析法，如VTEC时间序列分析法、二维扰动特征分析法、扰动速度分析法、小波变换频谱分析法及扰动方位分析法等，对各地震的同震电离层异常的共性特征进行分析。 （2）通过对地震发生期间的VTEC时空变化分析表明：同震电离层扰动出现的时间和扰动的振幅与震中距有关。震中附近区域电离层扰动出现在地震发生后的大约10~15min，随着震中距的增加，扰动出现的时间相对震中附近扰动滞后数分钟；同时扰动存在南北半球的不对称性，北半球地震的扰动在相对震中的北边扰动不明显，南半球地震的扰动在相对震中的南边扰动不明显。 （3）扰动传播速度及频谱关系变化特征表明：在地震发生后，电离层会出现不同的扰动源激发的不同类型的扰动，并且变化特征各有特点，由震源产生垂直向上的声重波，或由远离震源区域由瑞利波引起的二次声波。 （4）震中附近存在多方向扰动，并有一个主要扰动方向，即震中附近扰动存在两个传播方向，主要扰动方向的传播比另一个方向的传播更加明显，其主要扰动的传播路径与地球板块边线有关。

Outbreaks of natural disasters, such as earthquakes, usually cause ionospheric disturbances. Based on GNSS-VTEC technology, the disturbance characteristics and variation regularity of co-seismic ionospheric anomalies are analyzed, and the underlying mechanism is explored, which is of great scientific significance for seismic monitoring. The paper uses ground-based GNSS data to study the the ionospheric disturbance characteristics and variation laws of earthquakes in New Zealand and Nepal, which are located in the southern and northern hemispheres respectively, and deeply analyses their common characteristics, and verifies the results by the Chilean earthquake in the southern hemisphere. The main contents and results of the study are summarized as follows: (1) Using the dual-frequency carrier phase observation to obtain the VTEC during each earthquake occurrence, we analyzed its disturbance variation，and this paper used the 4th order 2-8MHz bandpass filtering method to remove the ionospheric disturbance trend term interference . Finally, using a variety of perturbation feature analysis methods, such as VTEC time series analysis, two-dimensional perturbation feature analysis, disturbance velocity analysis, wavelet transform spectrum analysis and disturbance azimuth analysis, etc., the coseismic ionospheric anomalies of each earthquake Common features were analyzed. (2) Through the analysis of the VTEC spatio-temporal variation during the earthquake, it is shown that the time and disturbance amplitude of the coseismic ionospheric disturbance are related to the epicentral distance of the disturbance. The ionospheric disturbance in the vicinity of the epicenter occurred about 10~15 minutes after the earthquake. With the increase of the epicentral distance, the disturbance appeared to lag several minutes after the disturbance near the epicenter. At the same time, there exists an asymmetry of disturbance between the northern and southern hemispheres .The disturbance in the north of the relative epicenter is not obvious, and the disturbance of the southern hemisphere earthquake is not obvious in the south of the relative epicenter. (3) The characteristics of disturbance propagation velocity and spectral relationship change indicated that after the earthquake , different types of disturbances were excited by different disturbance sources and then appeared in the ionosphere, with diverse characteristics. The vertical and upward acoustic heavy waves are generated by the source. Or the second ionospheric disturbance trend term interference sound waves are caused by Rayleigh waves away from the source area. (4) There are multi-directional disturbances near the epicenter, and there is a main disturbance direction, that is, there are two propagation directions in the vicinity of the epicenter. The propagation of the main disturbance direction is more obvious than that of the other direction. The main disturbance propagation path and the earth plate are related to the sideline.