基于CEEMD-Wavelet-SavGol模型的GPS多路径修正算法

GPS Multipath Correction Algorithm Based on CEEMD-Wavelet-SavGol Model

针对GPS多路径提取过程中EMD算法存在模态混叠效应及小波(Wavelet)去噪局限性的问题,提出了一种基于CEEMDWavelet-SavGol模型的多路径提取算法。为了能够充分提取高频和低频中的有用信息,该算法利用完备经验模态分解(CEEMD)对信号进行分解,得到一系列从高频到低频的模态函数(IMF),并根据模量标准化累计均值法对尺度进行区分,然后分别采用Wavelet和SavGol滤波对高频分量和低频分量进行降噪,将降噪后的IMF进行重构,得到降噪后的信号。最后将该模型用于GPS多路径误差提取的实例中,并与Wavelet、EMD、CEEMD模型进行对比,证明了新模型的有效性。

A new algorithm based on CEEMD-Wavelet-SavGol model was proposed in view of the problem that the EMD algorithm has the mode mixing effect and the Wavelet denoising has some limitations. In order to fully extract the useful information from the highfrequency component and low-frequency components,the proposed algorithm could decompose signal using complete empirical mode decomposition（CEEMD） to get a series of intrinsic mode functions（IMF） from high to low frequency. Then the scale could be distinguished according to the mean of standardized accumulated modes（MSAM）. And then the low-frequency and high-frequency components were denoised by wavelet and SavGol filter. The denoised signal would be obtained after IMFs reconstruction. At last,the proposed model was applied to GPS multipath error extraction,and the validity of the new model was proved compared with Wavelet,EMD and CEEMD model.