针对提出的故障信号，利用awgn加噪，对其进行小波软硬阈值降噪，提出一种改进阈值，利用五种自适应阈值函数sqtwolog、rigrsure、heursure、minimaxi和ddencmp中阈值选取原则，对软阈值、硬阈值和改进阈值进行降噪效果对比。(In view of the proposed fault signal, the wavelet soft and hard threshold de-noising is carried out by AWGN adding noise, an