一种分析光纤传感串扰效应的蒙特卡罗方法

Monte-Carlo Method Analyzing Crosstalk Effect in Fiber Sensing

为提高光纤传感系统的复用能力,常将多个谱型重叠的传感器串联,由此引发的串扰效应会导致测量误差的产生,从而需要对串扰效应进行深入分析。将蒙特卡罗法引入到由多个谱型重叠传感器串联组成系统的研究中,该方法能考虑到光谱阴影、任意阶多次反射的串扰效应,计算出系统总反射率谱等信息。为验证方法的可靠性,使用蒙特卡罗法对由两个谱型重叠的传感器串联所组成系统的总反射率谱进行了仿真,并与其数学解析解比较,结果显示两者吻合度高,在选择光线数为5×106时,计算误差量级在10-3左右,证实了该方法的准确性。在此基础上,采用蒙特卡罗法对无解析解的多个传感器串联所组成系统的总反射率谱进行了仿真计算。

In order to improve the multiplexing capacity of fiber sensing system, several sensors with overlapped spectra are always connected in series. However, crosstalk effects introduced by serial connections will lead to measurement errors, which means that crosstalk effects between sensors should be well researched. The Monte-Carlo method is introduced to analyze the system composed of several serial sensors with overlapped spectra. This method can take crosstalk effects like spectrum shadowing and arbitrary-order multiple reflections into account and calculate the reflectivity spectrum of the system. In order to verify the reliability of the Monte-Carlo method, reflectivity spectra of a system composed of two serial sensors are calculated by the analytic solution and the Monte-Carlo method, respectively. As the number of light beams set to be 5 × 10^6 , the calculate error level is about 10^- 3. The comparison indicates that the two methods have a good agreement, approving the accuracy of the Monte-Carlo method. The reflectivity spectrum of a system composed of more than two serial sensors which have no analytic solution is also analyzed by the Monte-Carlo method.