Olsson Samuel L I, Karlsson Magnus, Andrekson Peter A
Opt Express. 2015 May 4;23(9):11724-40. doi: 10.1364/OE.23.011724.
We investigate the impact of in-line amplifier noise in transmission systems amplified by two-mode phase-sensitive amplifiers (PSAs) and present the first experimental demonstration of nonlinear phase noise (NLPN) mitigation in a modulation format independent PSA-amplified transmission system. The NLPN mitigation capability is attributed to the correlated noise on the signal and idler waves at the input of the transmission span. We study a single-span system with noise loading in the transmitter but the results are expected to be applicable also in multi-span systems. The experimental investigation is supported by numerical simulations showing excellent agreement with the experiments. In addition to demonstrating NLPN mitigation we also present a record high sensitivity receiver, enabled by low-noise PSA-amplification, requiring only 4.1 photons per bit to obtain a bit error ratio (BER) of 1 × 10(-3) with 10 GBd quadrature phase-shift keying (QPSK) data.
我们研究了由双模相敏放大器（PSA）放大的传输系统中在线放大器噪声的影响，并首次在调制格式无关的PSA放大传输系统中进行了非线性相位噪声（NLPN）抑制的实验演示。NLPN抑制能力归因于传输跨度输入端信号波和闲波上的相关噪声。我们研究了一种在发射机中有噪声加载的单跨度系统，但预计结果也适用于多跨度系统。数值模拟支持了实验研究，模拟结果与实验结果显示出极好的一致性。除了演示NLPN抑制，我们还展示了一种创纪录的高灵敏度接收机，该接收机由低噪声PSA放大实现，在10 GBd正交相移键控（QPSK）数据下，每比特仅需4.1个光子就能获得1×10⁻³的误码率（BER）。
