基于小波变换的高斯曲线拟合在峰值定位中的应用

针对低速率解调仪采样获得光纤布喇格光栅反射光谱解调精度低的缺点,采用了一种基于小波变换的高斯(WTG)曲线拟合方法。利用小波变换对反射光谱信号进行分解,对小波细节分量进行阈值量化处理,在此基础上,运用处理后的细节分量和近似分量对信号进行重构;然后对重构后的信号插值并进行高斯曲线拟合,使用Levenberg-Marquardt(LM)算法优化高斯拟合系数。仿真实验结果表明:与直接寻峰算法、高斯拟合算法相比,WTG算法的峰值定位误差最小,解调精度更高。

Application of wavelet transform-based Gauss curve fitting in peak positioning

To overcome the disadvantage of low demodulation accuracy of reflective spectrum of fiber Bragg grating sampled by portable demodulator,a wavelet transform-based Gaussian(WTG)curve fitting method is introduced.The reflection spectrum signal is decomposed by wavelet transform,and the wavelet detail component is quantized by threshold.On this basis,the signal is reconstructed by the processed detail component and approximate component.Then,the reconstructed signal is interpolated to fit the Gauss curve,and the Levenberg-Marquardt(LM)algorithm is used to optimize the Gauss fitting coefficient.The simulation results show that the WTG algorithm has the smallest peak positioning error and higher demodulation accuracy compared with the direct peak seeking algorithm and the Gauss fitting algorithm.