用于光纤传感的可调半软阈值小波去噪算法

针对大容量超弱FBG传感网络解调系统的干涉噪声和固有电子学噪声,基于传统小波阈值算法去噪时软、硬阈值函数存在恒定偏差及连续性差的缺点,提出一种改进的小波阈值去噪算法。该算法引入了调解因子和半软阈值因子,完成向软、硬阈值函数的转变,保证了连续性且降低重构误差。仿真结果表明,该函数不仅在连续性上优于传统的阈值函数,重构时对信号的还原度较高,信噪比(SNR)相比于软、硬阈值函数均有所提高,平均提升了0.1034 dB、2.4327 dB,而均方根误差(RMSE)相比于软硬阈值函数均有所降低,平均降低了0.1665、0.1687。新阈值函数相比于传统阈值算法能够获得更优良的去噪效果,可为光纤布拉格光栅传感网络高精度寻峰解调去噪提供参考。

An adjustable semi-soft threshold wavelet denoising algorithm for optical fiber sensing

Aiming at the interference noise and inherent electronic noise of large capacity ultra-weak FBG sensor network demodulation system,an improved wavelet threshold denoising algorithm is proposed,which is soft and hard threshold function constant deviation and poor continuity when traditional wavelet threshold algorithm is used to denoise.The algorithm introduces mediation factor and semi-soft threshold factor to complete the transformation to soft and hard threshold function,the continuity is guaranteed and the reconstruction error is reduced.The simulation results show that the function not only superior to the traditional threshold function in continuity,but also has a high degree of signal reduction in reconstruction.The signal-to-noise ratio(SNR) is improved compared with the soft and hard threshold functions,and the average increase is 0.1034 dB,2.4327 dB.Compared with the soft and hard threshold function,the root mean square error(RMSE) is reduced by 0.1665 and 0.1687.Compared with the traditional threshold algorithm,the new threshold function can obtain better denoising effect,and can provide a reference for high precision peak-finding demodulation and denoising in fiber Bragg grating sensor networks.