基于WDM-PON架构的5G前传系统中的FWM效应

FWM Effect in 5G Fronthaul Transmission System Based on WDM-PON Architecture

为了应对快速增长的带宽需求,解决非线性效应限制波分复用无源光网络(wavelength-division multiplexing passive optical network,WDM-PON)系统的传输距离和信道容量,尤其是四波混频(four-wave mixing,FWM)效应的问题。通过实验与仿真研究了25 Gb·s·λ非归零码(non-return-to-zero,NRZ)信号经过25 km标准单模光纤(standard single-mode fiber,SSMF)传输时,FWM效应对系统所产生的影响。仿真结果表明,在信道间隔为200 GHz的12个波长传输系统中,除了第一个和最后一个信道之外,其他信道误码率(bit error rate,BER)都不能达到前向纠错码(forward error correction,FEC)的门限1.0×10。因此,在制定5G前传系统波长分布和信道间隔时,应充分考虑FWM串扰。

Wavelength-division multiplexing passive optical network (WDM-PON) is considered as a mainstream solution for 5G fronthaul transmission system to cope with the rapidly increasing demand of bandwidth.However,nonlinearity effects,especially the fourwave mixing (FWM) effect in WDM-PON systems will impair system performances in the transmission distance and channel capacity.In this paper,the influence of FWM effect on multi-wavelength system with 25 Gb·s·λnon-return-to-zero (NRZ) signal over 25 km standard single-mode fiber (SSMF) transmission is explored by experiment and simulation.Study results show that in a 200 GHz spaced 12-channel system,the bit error rate (BER)of all channels,except for the first and last channels,cannot reach the threshold 1.0×10of forward error correction (FEC).This implies that FWM crosstalk should be given full consideration while making wavelength plans for 5G fronthaul system,including the wavelength distribution and channel spacing selection.