基于DSP的光纤布拉格光栅波长解调系统

Fiber Bragg Grating Wavelength Demodulation System Based on DSP

波长解调技术是光纤布拉格光栅在温度、应变测量等领域应用的关键技术,提出并实现了一种基于可调谐Fabry-Perot滤波器的波长解调系统设计方案.系统使用扫描控制信号作用于可调谐Fabry-Perot滤波器,DSP对扫描控制电压和布拉格光栅的反射波峰进行采样与处理,通过标准具和参考光栅对Fabry-Perot滤波器进行标定,使用数字滤波提高了数据的稳定性和分辨率.实验表明,该系统的解调效果很好,在结构简单的基础上能取得较好的精度与分辨率.

Wavelength demodulation is the key technology in temperature and strain measurement using Fiber Bragg Grating sensors. An approach of wavelength demodulation system based on Fabry-Perot tunable filter is proposed and demonstrated. A tunable Fabry-Perot filter is controlled by scanning signal. The Digital Signal Processor synchronously performs data gathering and processing on the scanning signal and the wave crest reflected by Fiber Bragg Grating. Reference filter and reference FBG are used to calibrate the tunable Fabry-Perot filter. System stabilization and resolution are improved by using a digital filter algorithm. It＇s proved by experiment that this system has a good performance in wavelength demodulation, and good resolution can be achieved with simple configuration.