In this paper, we identified and discussed several concerns for the deployment of distributed Raman amplifiers, including gain impairments in a typical fiber network and the risk of high optical pump power. Additionally, we proposed several recommendations for accommodating these issues. The recommendations are as follows. 1. Set a loss budget for panel loss and splice loss, and inspect/repair the fiber plant as necessary. 2. The panel loss should be less than 1dB, while the splice loss should be less than 0.2dB for a hybrid Raman system and 0.1dB for an all-Raman system. 3. Fiber loss at signal and pump wavelengths should be characterized throughout the fiber plant. 4. Raman amplifiers should only be deployed if they have the ability to automatically adapt to unique fiber loss characteristics. 5. Raman amplifiers should only be deployed if they have auto-shutdown capability on the pump. 6. All technicians should wear appropriate eye protection when operating on Raman systems. 7. A thorough connector cleaning procedure should be written and implemented. 8. The potential for metallic particles entering into the optical path should be eliminated. 9. Fire-proof patch cables should be used whenever possible. In addition to following these recommendations, network operators can more confidently deploy Raman amplification by utilizing the two mitigation techniques proposed and experimentally demonstrated in this paper. First, we showed that by using 3dB power splitters to divide the pump power between a forward propagating span and a backward propagating span, the maximum localized pump power could be cut in half without decreasing the gain. This technique not only increases the safety of Raman amplifiers, it also increases the OSNR by about 6dB. The second technique that we demonstrated uses higher order pumping to reduce the noise power by 1.5dB. This technique is useful in a case where the amplifier must increase the lower-wavelength optical pump in order to compensate for high water peak loss, which can degrade the noise performance.
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