不同采样方式下光纤布喇格光栅反射谱寻峰算法的分析

Analysis of Peak-detection Algorithms in Fiber Bragg Grating by Different Sampling Methods

对光纤布喇格光栅反射谱的三种寻峰算法(三次样条插值数值微分法、高斯-多项式拟合法和高斯拟合法)进行了分析和比较;相同采样情况下,得出了高斯拟合法确定的峰值准确度最高的结论;采样点数为250的均匀采样中,三种算法寻峰结果对实际值的误差分别为:3.4pm、13.0pm和2.6pm.引入了非均匀数据采集的寻峰思路,分别应用三种寻峰法对实际光栅的反射谱分别进行均匀采集和非均匀采集.结果表明,对于相同寻峰方法在非均匀数据采集下获得的峰值更精确,采样点数为250时,高斯拟合法寻峰时非均匀采集对应的误差比均匀采集减少了38.46%.

Three peak-detection algorithms(cubic spline interpolation differential method,Gauss polynomial,Gaussian fitting algorithm) for fiber Bragg grating reflection spectrum were analyzed and compared.It is demonstrated that Gaussian fitting algorithm produces the lowest error under the same sampling conditions;when the uniform sampling number is 250,the errors of three peak-detection algorithms are respectively 3.4 pm,13.0 pm and 2.6 pm.The idea of non-uniform data sampling method to search peak was proposed.Sample the actual FBG reflection spectrum with uniform and non-uniform sampling method,and search peak using the three peak-detection algorithms respectively.It can be concluded that the error of a certain algorithm by non-uniform sampling is lower than by uniform sampling method;when the sampling number is 250,FBG peak error of Gaussian fitting algorithm under non-uniform sampling method is reduced by 38.46% than uniform sampling method.