Abstract

FLCS-PON is a concept of a flexible passive optical network (PON), where the modulation and coding parameters of the downstream signal, consisting of modulation order, code rate, and probabilistic shaping entropy, can be adjusted on a timeslot basis to opportunistically achieve mean net bitrate increase. The system harnesses unused margins of transceivers and optical distribution networks. In this work we describe the architecture of FLCS-PON, which is designed to leverage the 50G-PON ecosystem. We provide updated and accurate performance metrics for FLCS-PON low-density parity check (LDPC) forward error correction (FEC) codes. We then report on the operator trial of a FLCS-PON system prototype carried out jointly with Vodafone and demonstrate maximum achievable net bitrates as a function of the optical path loss for five different transmitter configurations (non-return-to-zero, PAM-4, and probabilistically shaped PAM-4 with three different entropy values). On the receiver side we test four different configurations: ${\rm{FFE23}}\;{ + }\;{\rm{DFE5}}$ or ${\rm{FFE16}}\;{ + }\;{\rm{DFE1}}$ equalizers, each followed by either a hard- or a soft-input LDPC decoder. Finally, we consider two study cases on mean bitrates achievable with FLCS-PON over deployed optical distribution networks (ODNs). We map net bitrates obtained during the operator trial to Vodafone’s actual ODN optical path loss probability distribution or an ensemble of simulated ODNs. We show that in the majority of cases, FLCS-PON can provide a significant improvement of mean net bitrate. Further, FLCS-PON also enables extension of nominal power budget classes, beyond guaranteed conventional ODN loss, making it possible to provision links that might otherwise be unsupported by conventional PON.

© 2022 Optica Publishing Group

Experimental demonstration of flexible information rate PON beyond 100 Gb/s with probabilistic and geometric shaping

Noriaki Kaneda, Rui Zhang, Yannick Lefevre, Amitkumar Mahadevan, Doutje van Veen, and Vincent Houtsma
J. Opt. Commun. Netw. 14(1) A23-A30 (2022)

Perspectives on and the road towards 100  Gb/s TDM PON with intensity-modulation and direct-detection

Rene Bonk, Ed Harstead, Robert Borkowski, Vincent Houtsma, Yannick Lefevre, Amitkumar Mahadevan, Dora van Veen, Michiel Verplaetse, and Sheldon Walklin
J. Opt. Commun. Netw. 15(8) 518-526 (2023)

Real-time validation of downstream 50G/25G and 50G/100G flexible rate PON based on Miller encoding, NRZ, and PAM4 modulation

Doutje van Veen and Vincent Houtsma
J. Opt. Commun. Netw. 15(8) C147-C154 (2023)

Principle and strategy of using probabilistic shaping in a flexible coherent passive optical network without optical amplifiers

Sizhe Xing, Guoqiang Li, An Yan, Wangwei Shen, Zhongya Li, Jiaye Wang, Jianyang Shi, Zhixue He, Nan Chi, and Junwen Zhang
J. Opt. Commun. Netw. 15(8) 507-517 (2023)

End-to-end deep learning for a flexible coherent PON with user-specific constellation optimization

Sizhe Xing, Zhongya Li, Changle Huang, Guoqiang Li, Aolong Sun, An Yan, Wangwei Shen, Jianyang Shi, Ziwei Li, Chao Shen, Nan Chi, and Junwen Zhang
J. Opt. Commun. Netw. 16(1) 59-70 (2024)