50G-PON平滑演进的挑战和方案研究

摘要：提出了50G-PON三代时分共存系统架构，以解决以太网无源光网络（EPON）、10G-EPON向50G-PON演进中因兼容现网非收窄EPON终端所面临的波长冲突等关键问题，实现了EPON收窄/非收窄、10G-EPON对称/非对称以及50G-PON对称/非对称6类终端全兼容共存。研究涵盖下行1 366 ± 2 nm新波长与上行1.25 Gbit/s、10.312 5 Gbit/s、24.883 2 Gbit/s、49.766 4 Gbit/s四速率时分接收等物理层关键技术，并完成了相应光模块与系统设备的研制及验证测试。结果表明，所研光模块与系统指标满足现网29 dB功率预算要求并留有余量，可支持现网光分配网络（ODN）“零改动”平滑升级。本研究成果为万兆光网演进提供了高效益、低成本且可持续的解决方案。

关键词：50G-PON；EPON；10G-EPON；时分复用；三代共存；四速率突发接收机

Abstract: A three-generation time-division coexistence system architecture for 50G-passive optical network (PON) is proposed to address challenges including wavelength conflicts during the evolution from Ethernet PON (EPON) and 10G-EPON to 50G-PON, while ensuring backward compatibility with deployed non-narrowed EPON terminals. This architecture enables full coexistence among six classes of terminals: narrowed and non-narrowed EPON, symmetric and asymmetric 10G-EPON, and symmetric and asymmetric 50G-PON. Key physical-layer technologies were investigated, such as a newly defined 1 366±2 nm downstream wavelength and an upstream four-rate (1.25 Gbit/s，10.312 5 Gbit/s，24.883 2 Gbit/s, 49.766 4 Gbit/s) time-division reception scheme. Corresponding optical modules and system equipment for the three-generation coexistence were developed and validated. Test results show that the optical interface specifications of the module and the system performance satisfy the existing network's 29 dB power budget requirement with sufficient margin, thereby supporting a smooth, zero-touch evolution of the installed optical distribution network (ODN). An efficient, cost-effective, and sustainable solution is thus provided for the evolution toward 10G-class optical access networks.

Keywords: 50G-PON; EPON; 10G-EPON; time-division multiplexing; three-generation coexistence;  four-rate burst receiver