摘要
现有的拉曼光纤温度传感系统大多为多模系统,由于单模光纤传输损耗较小,采用单模光纤可以使测量范围轻易扩展。但由于单模光纤中产生的自发拉曼散射信号特别微弱,完全被淹没在噪声中,影响了系统的测温精度。针对存在的噪声信号问题,提出采用现有的累加平均算法与小波变换相结合的信号处理方法对拉曼散射信号进行处理。采用db5小波函数,分解层数为5层。通过matlab上进行仿真,结果表明信号处理方法可以有效地消除信号中的噪声,同时又能很好地保留有用信号,缩短了系统的测量时间,改善了系统的性能指标。
The existing Raman temperature sensing system of optical fiber is mostly multi - mode system. Due to the smaller loss of single - mode fiber transmission, the measuring range can be easily extended by using single - mode fiber. However, the spontaneous Raman scattering signals are particularly weak in single - mode fiber, completely submerged in the noise, and affecting the system＇s temperature measurement aeeuraey. To solve this problem, this paper proposes a cumulative average algorithm and a wavelet transform signal processing method to process the Raman scattering signal. Db5 wavelet function is used with five decomposition layers. By matlab simulating, the results show that the signal processing method can eliminate signal noise effectively, retain desired signal very well, shortenthe system＇s measurement time and improve the system performance.
出处
《计算机仿真》
CSCD
北大核心
2010年第3期366-370,共5页
Computer Simulation
关键词
拉曼
单模光纤
累加平均
小波去噪
Raman
Single - mode fiber
Cumulative average
Wavelet de - noising
