利用波长为９０５ｎｍ，ＧａＡＳ大功率半导体脉冲激光器为泵浦光源，采用光时域反射ＯＴＤＲ（ＯｐｔｉｃａｌＴｉｍｅ－ＤｏｍａｉｎＲｅｆｌｅｃｔｏｍｅｔｒｙ）技术，以及高速采样平均技术对芯径为５０／１２５μｍ，１ｋｍ长的ＧＩ多模光纤的后向散射光光谱进行了分析与测量．着重研究了光谱成份中，强度仅为入射光强的１０－８～１０－９极其微弱的反斯托克斯散射光的温度特性及其应用—分布光纤温度传感系统． GaAs high-power semiconductor pulsed laser is used as pump light source. The optical time-domain reflectometry OTDR (Optical Time-DomainReflectometry) technology and high-speed sampling averaging technique are used to measure the performance of GI multimode fiber with a diameter of 50/125 μm and a length of 1 km Backscattered light spectra were analyzed and measured. The temperature characteristics of anti-Stokes scattering light whose intensity is only 10-8 ~ 10-9 whose intensity is only 10-8 ~ 10-9 in the spectral composition and its application - distributed optical fiber temperature sensing system are mainly studied.