利用光脉冲在非线性光纤中传播时所满足的波动方程,导出了在拉曼效应和参量放大共同作用下,激光脉冲在低双折射光纤中传输时所满足的耦合模方程。给出了沿光纤的快轴输入线偏振光抽运时,在拉曼效应和参量放大共同作用下的增益。结果表明,拉曼效应可导致参量放大下的斯托克斯波与反斯托克斯波的增益谱由对称变为不对称。输入不同的功率或传输常数差,增益谱的峰值和位置均会随之发生变化。 By using the wave equation which the pulse propagates in the nonlinear fiber, the coupled mode equation which is satisfied when the laser pulse propagates in the low birefringence fiber is deduced under the combination of Raman effect and parametric amplification. The gain of polarized light input along the fast axis of fiber is given under the combined effect of Raman effect and parametric amplification. The results show that the Raman effect can cause the gain spectrum of Stokes and anti-Stokes waves under parametric amplification to change from symmetrical to asymmetric. Enter a different power or transmission constant difference, the peak and position of the gain spectrum will change.