设计了基于拉曼光时域反射技术的船舶电缆分布式光纤测温系统。为了有效提高信号强度,系统硬件设计中改进了微弱光信号的探测及放大电路,并且基于FPGA+DSP高速数据处理模块来加快数据处理速度;针对拉曼反射信号信噪比低的特点,系统对采集信号采用数字累加平均与自适应阈值小波滤波相结合的去噪方法,在改善信噪比的同时缩短了测温时间。实验表明,设计系统测温距离达4km,空间分辨率为1.5m,温度分辨率为0.1℃,系统响应时间为3.8s,满足设计要求,且综合指标优异。 A ship cable distributed optical fiber temperature measurement system based on Raman time-domain reflectometry was designed. In order to improve the signal strength effectively, the detection and amplifying circuit of weak optical signal is improved in the hardware design of the system, and the speed of data processing is accelerated based on FPGA + DSP high-speed data processing module. In view of the low signal-to-noise ratio of Raman reflection signal, Acquisition signal using digital cumulative average and adaptive threshold wavelet filtering denoising method combined to improve the signal to noise ratio at the same time shorten the temperature measurement time. Experiments show that the designed system has a temperature measuring distance of 4km, a spatial resolution of 1.5m, a temperature resolution of 0.1 ℃ and a system response time of 3.8s, which meets the design requirements and has excellent comprehensive indexes.