基于经验模态分解的GPS多径噪声抑制方法

GPS Multipath Noise Control Method Based on Empirical Modal Decomposition

针对GPS短基线差分测量中的多径效应问题,提出一种基于经验模态分解(Empirical Mode Decomposition,EMD)的GPS序列多径噪声抑制方法。首先,利用EMD对接收到的GPS序列进行自适应分解,得到各个包含不同信息的本征模函数(Intrinsic Mode Function,IMF);然后,利用奇异值分解方法对各个IMF进行分析并利用特征值谱的熵特征对IMF中的信号分量和噪声分量进行自动识别;最后,利用识别出的信号分量重构出多径噪声抑制后的GPS序列。采用仿真和实测数据开展实验对所提方法进行验证,实验结果与小波方法进行对比,结果表明,所提方法可以获得更好的多径噪声抑制性能。

A multipath noise suppression method based on empirical mode decomposition(EMD)for GPS short baseline differential measurement is proposed.First,EMD is used to adapt the received GPS sequence to obtain intrinsic mode functions(IMF)containing different information.Then the singular value decomposition method is used to analyze each IMF and the signal component and noise component in the IMF are automatically identified using the entropy characteristics of the eigenvalue spectrum.Finally,the GPS sequence after multipath noise suppression is reconstructed using the identified signal component.The proposed method is validated by simulation and experimental data,and the experimental results are compared with the wavelet method.The results show that the proposed method can obtain better performance of multipath noise suppression.