格网优化选站的Kriging重构全球电离层及精度分析

Kriging reconstruction of global ionosphere by grid optimization station selection and precision analysis

针对IGS卫星接收站点数量多、接收卫星数据质量参次不齐的问题,本文提出格网优化选站法,通过格网的大小控制每个区域测站的数量,并采用格网算法优先选择格网内数据质量高的测站下载数据,使用Kriging插值及反距离加权方法重构优化区域电离层,并与CODE电离层产品进行对比,评价重构电离层的精度。试验结果表明,格网选站不仅保证了全球测站均匀分布,而且在提高精度的同时,减小了计算量;Kriging内插重构电离层较反距离加权算法,能更好地弥补测站稀疏所引起的电离层延迟异常值的问题,解算的电离层延迟量的精度更高。

According to the problem that there are too many IGS satellite receiving stations and uneven quality level of received satellite data,this paper proposes a grid optimization station selection method,which controls the number of stations in each region through the size of the grid,and the paper uses the grid algorithm to preferentially pick the station downloaded data with high quality data in the grid,uses Kriging interpolation and inverse distance weighting method to reconstruct the optimized regional ionosphere,and compares it with the CODE ionosphere product to evaluate the accuracy of the reconstructed ionosphere.The experiment proves that the grid station selection not only ensures the uniform distribution of global stations,but also improves the accuracy and reduces the calculation amount.Kriging interpolation reconstruction ionosphere is better than the inverse distance weighting algorithm to compensate for the problem of ionospheric delay anomaly caused by station sparseness,and the accuracy of the ionospheric delay is also greatly improved.