组合EMD和PCA的多路径改正方法

多路径效应及高频随机噪声是目前影响GPS变形监测精度的主要因素。针对GPS变形监测中的多路径效应与高频随机噪声的周日重复性特征,提出了EMD(Empirical Mode Decomposition)与PCA(Principal Component Analysis)组合的GPS噪声改正方法。该方法先通过EMD对各天数据剔除高频随机噪声,再采用PCA对相关性较强的多路径效应进行提取和消除。实测数据分析表明,该组合方法能有效地削弱多路径效应及高频随机噪声,较单一滤波方法具有一定的优越性。

Multipath correction method by combining EMD and PCA

Multipath effects and high-frequency random noise are the main errors which influence the accuracy of GPS deformation monitoring. According to the noise characteristics, this paper proposes an integrated noise correction method based on Empirical Mode Decomposition （EMD） filtering and the Principal Component Analysis （PCA）. Firstly, the EMD method is used to diminish the high-frequency random noise of each day, and PCA is used to extract and eliminate the high-correlation multipath effects. Experiment data shows that the combined method can effectively weaken the multipath effect and high frequency random noises, and is superior to either single filtering method.