Tong Zhi, McKinstrie C J, Lundström Carl, Karlsson Magnus, Andrekson Peter A
Photonics Laboratory, Department of Microtechnology and Nanoscience, Chalmers University of Technology, SE-412 96 Göteborg, Sweden.
Opt Express. 2010 Jul 19;18(15):15426-39. doi: 10.1364/OE.18.015426.
Based on semi-classical theory, the noise performance of a multi-span fiber optical transmission system employing a cascaded phase-insensitive amplifier (PIA) and phase-sensitive amplifiers (PSAs) is investigated. Compared with the pure-PIA and pure-PSA based in-line amplification schemes, the copier + PSA scheme is found to improve the system NF by up to 6 and 3 dB, respectively, in an optimized long-haul fiber link. In addition, this cascaded configuration will significantly relax the requirement for accurate phase- and wavelength-locking which is rigorously needed in the pure-PSA configuration. This scheme is also modulation-format independent. As a proof of concept, the NF of a fiber parametric amplifier based copier + PSA cascade with inter-stage attenuation representing the fiber link is measured, which shows a 1.8-dB total NF improvement over the conventional EDFA cascade.
基于半经典理论，研究了采用级联相位不敏感放大器（PIA）和相位敏感放大器（PSA）的多跨段光纤传输系统的噪声性能。与基于纯PIA和纯PSA的在线放大方案相比，发现在优化的长距离光纤链路中，复印机+PSA方案分别可将系统噪声系数提高多达6 dB和3 dB。此外，这种级联配置将显著放宽对精确相位和波长锁定的要求，而这在纯PSA配置中是严格需要的。该方案也与调制格式无关。作为概念验证，测量了基于光纤参量放大器的复印机+PSA级联（级间衰减代表光纤链路）的噪声系数，结果表明与传统掺铒光纤放大器（EDFA）级联相比，总噪声系数提高了1.8 dB。
