基于波长变换的概率整形正交频分复用光信号传输系统

Probabiliy Shaping Orthogonal Frequency Division Multiplexing Optical Signal Transmission System Based on Wavelength Conversion

本文首先从理论上分析了在共极化双泵浦方案中,波长转换不会改变概率整形(PS)信号的概率分布,并且正交频分复用(OFDM)信号子载波的顺序可以保持不变的原因。然后,通过实验验证了全光波长转换后,PS-64QAM-OFDM信号通过高非线性光纤在零差相干检测系统中的传输。最后,通过实验证明,当波特率为20 Gbaud、误码率为1×10^(-2)时,普通64QAM信号的光信噪比(OSNR)损耗为1 dB,PS-64QAM信号的OSNR损耗改善了0.5 dB。

This study theoretically analyzed the reasons why,in the copolarized dual-pump scheme,wavelength conversion does not change the probability distribution of the probability shaping (PS) signal and the order of orthogonal frequency division multiplexing (OFDM) signal subcarriers can remain unchanged.Then,after all-optical wavelength conversion,the transmission of the PS-64QAM-OFDM signal through a highly nonlinear optical fiber in a homodyne coherent detection system was experimentally verified.Finally,the experimental results indicate that when the baud rate is20 Gbaud and the bit error rate is 1×10^(-2),the optical signal-to-noise ratio (OSNR) loss of an ordinary 64QAM signal is1 dB,and the OSNR loss for PS-64QAM signal is improved by 0.5 dB.