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将多波长激光光源技术引入瑞利布里渊光时域分析系统，其中抑制载波的微波调制多波长脉冲基底1 阶边带在传感光纤中产生的多波长背向瑞利散射作为探测光与多波长传感脉冲发生受激布里渊散射作用，可有效地提高光纤 SBS 阈值和 SBS 作用效率、系统信噪比和布里渊频移测量精度。分析了相位调制器产生多波长激光光源、电光强度调制器产生作为探测光的多波长斯托克斯和反斯托克斯光的激励光的原理，建模分析了多波长瑞利布里渊光时域分析系统原理，给出了系统信噪比与波长数关系的表达式；搭建单波长和三波长光纤 SBS 阈值测量系统及瑞利布里渊光时域分析系统，测量了光纤的 SBS 阈值和系统性能。实验结果表明，三波长较单波长系统光纤 SBS 阈值提高 3 倍，当单波长与三波长瑞利布里渊光时域分析系统均设定为传感脉冲宽度 100 ns、单个波长的脉冲峰值功率 100 m W，单个波长的脉冲基底功率 1.3 m W，传感光纤长度 2.4 km 时，信噪比提高 2.83 倍，在 2 km 光纤上布里渊频移波动从 33.4 MHz 降低为 15.6 MHz。
The multi-wavelength laser light source technology is introduced into the Rayleigh Brillouin optical time-domain analysis system, in which the multi-wavelength back-facing Rayleigh scattering generated by the first-order sideband of the microwave modulated multi-wavelength pulse substrate of the carrier wave is detected as the probe light and Stimulated Brillouin scattering can occur in multi-wavelength sensing pulse, which can effectively improve the SBS threshold and SBS efficiency, system SNR and Brillouin frequency shift measurement accuracy. The principle of the phase modulator to generate multiwavelength laser source and the electro-optic intensity modulator to generate multi-wavelength Stokes and anti-Stokes light as probe light is analyzed. The multi-wavelength Rayleigh Brillouin Optical time-domain analysis system principle, the expression of the relationship between the signal to noise ratio and the number of wavelengths is given. The single-wavelength and three-wavelength optical SBS threshold measurement system and the Rayleigh Brillouin optical time-domain analysis system are set up to measure the SBS Threshold and system performance. Experimental results show that the SBS threshold of three-wavelength optical fiber is three times higher than that of single-wavelength optical fiber. When single-wavelength and three-wavelength Rayleigh Brillouin optical time-domain analysis system are set as the sensing pulse width of 100 ns, single-wavelength pulse peak power 100 mW. With a single wavelength of pulse substrate power of 1.3 mW, the SNR increases by 2.83 times when the sensing fiber length is 2.4 km. The fluctuation of Brillouin frequency shift from 33.4 MHz to 15.6 MHz over 2 km fiber is also observed.