基于高斯拟合的光纤法珀相关解调算法研究

Research on Optical Fiber Fabry-Perot Correlation Demodulation Algorithm Based on Gaussian Fitting

为了提高非扫描式互相关解调系统的解调精度,通过分析非扫描式解调系统的信号特征,研究了一种基于高斯拟合的解调算法.该算法使用最大值寻峰算法解调出峰值位置,提取出峰值位置附近的光强数据,利用高斯函数对提取出的数据进行曲线拟合,提高了解调的精度.仿真结果表明,该算法具有良好的解调稳定性、解调准确性以及一定的抗干扰能力,仿真中测得该算法的解调误差标准差能达到0.2886 nm.为了验证算法的实际解调效果,建立了基于现场可编程逻辑门阵列(FPGA)结合数字信号处理器(DSP)的硬件系统,对算法进行实际试验,试验结果表明,该算法拥有比较高的解调精度,解调结果均方差可达到1.6 nm,算法在DSP中的运行时间为700μs.

A demodulation algorithm have been proposed to improve the demodulation accuracy of the non-scanning cross-correlation demodulation system after analyzing the signal characteristics of the non-scanning demodulation system.This algorithm which based on gaussian fitting uses the maximum peak finding algorithm to demodulate the peak position and extract the light intensity data near the peak position.The Gaussian function is used to curve-fit the extracted data to improve the resolution of demodulation.The simulation results show that the algorithm has great demodulation stability,demodulation accuracy and certain anti-interference ability.The standard deviation of the demodulation error of the algorithm can reach 0.2886 nm in 1000 consecutive demodulation simulations.A hardware system based on field programmable logic gate array(FPGA)and digital signal processor(DSP)is established to test the algorithm.The experiment results show that the algorithm has high demodulation accuracy,the mean square error of the demodulation result can reach 1.6 nm,and the running time of the algorithm in DSP is 700μs.