为改善小波脊线法在低信噪比下提取二相编码信号脉内特征的性能,提出了一种改进的小波脊线脉内特征提取方法。该方法将魏格纳一威利变换与小波脊线法相结合,利用魏格纳一威利变换对噪声的抑制来改善信噪比,通过分析二相编码信号的小波脊线特征来得到脉内特征参数。仿真结果表明,该方法在低信噪比下仍能准确提取二相编码信号的脉内特征,具有明显优越性。
A modified wavelet ridge method is proposed to improve the performance of the wavelet ridge method in extracting the intrapulse characteristic of the BPSK signal at low signal to noise ratio (SNR). This method combines WVD and wavelet ridge. First, the SNR can be improved by using the WVD to reduce the additive noise embedded in the original signal. And then the intrapulse characteristic parameters can be gained by analyzing the wavelet ridge characteristics of the BPSK signal. The simulation results show that the intrapulse characteristic of the BPSK signal can be extracted well and truly at low SNR, and it has obvious superiority.