讨论了分时复用(TDM)抽运光纤拉曼放大器的增益平坦特性,基于拉曼增益谱理论,建立了光纤拉曼放大器的开关增益与光纤特性的关系表达式。通过数值模拟发现,信号增益平坦随抽运功率组合的不同有规律地起伏变化。通过优化抽运功率组合,实现了TDM抽运光纤拉曼放大器增益的平坦化。 The gain flatness characteristics of time division multiplexing (TDM) pumping fiber Raman amplifier are discussed. Based on the Raman gain spectrum theory, the relation between switching gain and fiber characteristics of fiber Raman amplifier is established. Through numerical simulation, it is found that the flatness of the signal fluctuates regularly with different combinations of pumping power. By optimizing the pumping power combination, the gain gain of the TDM pump fiber Raman amplifier is flattened.