The future-generation passive optical network (PON) physical layer, targeting 100 Gbps/wavelength, will have to deal with severe optoelectronics bandwidth and chromatic dispersion limitations. In this paper, largely extending our Optical Fiber Communication Conference (OFC) 2020 invited paper, we review 100 Gbps/wavelength PON downstream alternatives over standard single-mode fiber in the O- and C-bands, analyzing three modulation formats (PAM-4, partial-response PAM-4, and PAM-8), two types of direct-detection receivers (APD- and SOA $+$+ PIN-based), and three digital reception strategies (unequalized, feed-forward equalized, and decision-feedback equalized). We evaluate by means of simulations the performance of these alternatives under different optoelectronics bandwidth and dispersion scenarios, identifying O-band feasible solutions able to reach 20 km of fiber and an optical path loss of at least 29 dB over a wide wavelength range of operation. Finally, we compare two digitally precompensated modulation schemes that are highly tolerant of chromatic dispersion, showing a possible extension to C-band operation, preserving direct-detection and linear-impairment equalization at the optical network unit side.

中文翻译：

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使用直接检测和线性损害均衡的100 Gbps /λPON下行O和C频段替代方案[邀请]

面向100 Gbps /波长的下一代无源光网络（PON）物理层将必须应对严格的光电带宽和色散限制。本文在很大程度上扩展了2020年光纤通信会议（OFC）的邀请论文，我们回顾了O和C波段标准单模光纤上100 Gbps /波长PON下行替代方案，分析了三种调制格式（PAM-4 ，部分响应PAM-4和PAM-8），两种类型的直接检测接收器（APD和SOA $ + $ +基于PIN）和三种数字接收策略（不均衡，前馈均衡和决策） -反馈均等）。我们通过仿真评估了这些替代方案在不同光电带宽和色散情况下的性能，确定能够在较宽的工作波长范围内达到20 km的光纤和至少29 dB的光路损耗的O波段可行解决方案。最后，我们比较了两个对色散具有高度容忍性的数字预补偿调制方案，显示了对C波段操作的可能扩展，在光网络单元侧保留了直接检测和线性损害均衡。