基于小波变化阈值的光干涉信号去噪

为了提高参数估计的精确度，根据光反馈自混合干涉信号的特点，对光反馈自混合干涉信号进行了去噪研究。在多分辨分析小波阈值去噪的基础上，采用了一种改进的阈值函数，克服了硬阈值函数不连续的缺点，解决了软阈值函数中存在的恒定偏差，并且具有软硬阈值函数不可比拟的灵活性。构建了光反馈自混合干涉理论模型，通过对其仿真波形和实测波形的处理，比较了三种阈值函数的去噪效果。结果表明，无论是在去噪效果上，还是在信噪比增益和最小均方误差意义上均优于传统的软硬阈值方法。

Denoising Optical Interferometry Signal Based on Wavelet Transform Threshold

For improving the precision of the parameter estimate , a new de-nosing method is used to study the denoisng of optical feedback self-mixing interferometry signals according to the characteristics of the optical feedback self-mixing interference signal. Based on much resolutional analysis wavelet threshold de-noising method ,an improved threshold function is proposed. it overcomes the shortcomings of the hard threshold with discontinuous function ang solves the problem of the permanent bias in soft threshold function,and it is more elastic than the soft threshold and hard threshold function. The model of optical feedback self-mixing interferometry system is introduced in detail. Denoising simulation and measured signals prove that the improved threshold method can get better denoising effect. ,and the numerical results show it gives better mean-square-error performance and signal-noise-ratio gains than the soft and hard threshold methods.