采用符合ITU-T标准的C-波段40信道波分复用(WDM)光源对分布式拉曼放大器(DRA)的特性进行了实验研究。对不同抽运方式及不同光纤长度的分布式拉曼放大器性能作了较为详细的报道。在抽运功率相同的条件下,选用50 km单模光纤对比研究了不同抽运方式的拉曼放大器增益和噪声。通过对不同光纤长度的分布式拉曼放大器的实验研究发现,在较低抽运功率且输入信号功率较低的情况下,随着光纤长度增加,拉曼增益也增加,有效噪声系数减小。研究了分布式拉曼放大器对波分复用通信系统信噪比的改善,实验发现不同抽运功率下,拉曼放大器对系统信噪比的改善随抽运功率增加而增加,但是不成线性关系,而且最终会出现饱和。

In this paper, the performance of distributed Raman fiber amplifiers (DRA) with 40-channel wavelength division multiplexing (WDM) signals has been investigated. And the Raman fiber amplifiers with different pumping schemes and different fiber lengths have been reported. The gain and noise figures of the Raman fiber amplifier with 50 km of G.652 fiber have been compared at different pumping schemes. When the pump power and the signal power are not high enough, the Raman gain increases with the fiber length and the noise figure (NF) decreases with the fiber length. The optical signal to noise ration (OSNR) has also been investigated. It is found that the OSNR increases with the pump power, until saturated.