改进的半参数模型法在GNSS时间序列季节性信号提取中的应用  

The Application of Improved Semi-Parametric Model Method in Seasonal Signal Extraction of GNSS Time Series

作　　者：王方超 吕志平[1] 邝英才 李林阳[1] 吕浩[1] 李静静 WANG Fangchao;LYU Zhiping;KUANG Yingcai;LI Linyang;LYU Hao;LI Jingjing(Information Engineering University,Zhengzhou 450001,China;61618 Troops,Beijing 100000,China)

机构地区：[1]信息工程大学,河南郑州450001 [2]61618部队,北京100000

出　　处：《测绘科学技术学报》2020年第1期32-38,共7页Journal of Geomatics Science and Technology

基　　金：国家自然科学基金项目(06023907);国家重点研发计划项目(2016YFB0501701)。

摘　　要：GNSS基准站坐标时间序列具有明显的季节性变化。基于谐波函数模型的最小二乘拟合方法只能得到固定振幅的季节性信号,而真实的季节性信号其振幅是变化的。采用半参数模型进行季节性信号提取时又存在最优平滑因子确定困难、迭代速度慢的问题。提出一种赋相对权比的半参数模型,采用迭代更快速的黄金分割法与改进效率法相结合的策略确定最优平滑因子。通过模拟数据实验,验证了改进模型的可用性。实验表明:改进方法的计算效率明显提高,对于10 a长度的模拟数据,相较GCV函数法搜索速度提高68.1%,相较L-曲线法速度提高25.8%;计算精度较最小二乘法和半参数模型法均有提高,所得残差中没有明显的季节性信号。The GNSS reference station coordinate time series has obvious seasonal changes.The least squares method based on the harmonic function model can only solve the seasonal signal with fixed amplitude,but the amplitude of the real seasonal signal changes.When semi-parametric models are used for seasonal signal extraction,it is difficult to determine the optimal smoothing factor and the iteration speed is slow.A semi-parametric model with relative weight ratio is proposed in the paper.The optimal smoothing factor is determined by a combination of a faster iterative golden section method and an improved efficiency method.The simulation data experiments verify the usability of the improved model.Experiments show that the calculation efficiency of the improved method is significantly improved.For simulation data whose length is 10,the search speed of the improved method is 68.1%higher than that of the GCV function method and 25.8%faster than that of the L-curve method.The calculation accuracy of the improved method is lower than that of the least square method and the semi-parametric model method.Compared with the least square method and the semi-parametric model method,the calculation accuracy of the improved method is higher,and there is no obvious seasonal signal in the residual.

关 键 词：GNSS时间序列 季节性信号 最小二乘 半参数模型 平滑因子 

分 类 号：P228[天文地球—大地测量学与测量工程]