基于改进小波变换的火炮膛压测试降噪方法

Noise reduction method of gun bore pressure test based on improved wavelet transform pressure test

针对火炮膛压测试时易受恶劣测试环境影响的问题,提出了一种使用改进后的小波变换对膛压测试信号降噪的方法。基于对火炮膛压测试信号的时频分析,在结合小波变换传统阈值函数各自优势的基础上创建了新的小波降噪阈值函数。新的算法解决了硬阈值函数不连续导致重构信号时引入振荡的问题;同时克服了软阈值函数滤波时对信号高频分量削减过多的问题,对于火炮膛压信号的降噪有着明显的优势。为了检验新的滤波方法的有效性,采用了计算信噪比及均方差的方法评价改进后的滤波方法。结果表明,使用改进后的阈值函数对信号的降噪处理取得了更好的效果。

Aiming at the problem that gun chamber pressure test is easy to be affected by bad test environment,an improved wavelet transform is proposed to denoise the chamber pressure test signal.Based on the time-frequency analysis of gun bore pressure test signal,a new wavelet denoising threshold function is created based on the advantages of wavelet transform and traditional threshold function.The new algorithm solves the problem of oscillation caused by discontinuity of hard threshold function.At the same time,it overcomes the problem of reducing the high-frequency component of the signal by the soft threshold function,and has obvious advantages for the noise reduction of gun bore pressure signal.In order to test the effectiveness of the new filtering method,a method to calculate the signal-to-noise ratio and mean square deviation is proposed to evaluate the improved filtering method.The results show that the improved threshold function has better effect on signal noise reduction.