受激布里渊散射（ＳＢＳ）与多径干涉噪音（ＭＰＩ）是光纤ＡＭ－ＣＡＴＶ 外调制传输系统中主要的非线性现象，本文分析了激光器高频扰动抑制ＳＢＳ与ＭＰＩ的原理，导出了扰动对系统ＳＢＳ阈值提高量及ＭＰＩ抑制程度的理论公式，通过对扰动引起的激光器频率啁啾及附加强度调制而导致的色散的理论分析与计算，得到了扰动信号频率及幅度的选取原则． SBS and MPI are the main non-linear phenomena in AM-CATV system. In this paper, the principle of high-frequency disturbance rejection of SBS and MPI is analyzed, and the disturbance The theoretical formula for the threshold increase of SBS and the degree of MPI suppression are obtained. Theoretical analysis and calculation of chromatic dispersion caused by perturbation caused by laser frequency chirp and additional intensity modulation are carried out. The principle of selection of frequency and amplitude of perturbation signal is obtained.