BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20260625T040120EDT-4902VLvMox@132.216.98.100 DTSTAMP:20260625T080120Z DESCRIPTION:Abstract\n\nCoherent technology is a competitive candidate for next-generation 100/200-G passive optical networks (PON) with 40 km covera ge. The characteristics of linear optical field conversion\, digital compe nsation\, and superior receiver sensitivity enable coherent PON (CPON) to have higher capacity\, larger coverage extended reach\, and higher density support. The evolution of access networks' scale\, scalability\, and flex ibility leads to a series of dynamic behaviors in CPON. In this thesis\, t he selected topics related to potential business issues\, including rate f lexibility\, parameters monitoring\, dynamic encryption\, and service fair ness of downstream links over CPON are analyzed and demonstrated emphatica lly.\n\nThis thesis first explores and demonstrates point-to-point (P2P) a nd point-to-multipoint (P2MP) coherent optical communication systems and a ccess networks. A time-variant entropy-regulated probabilistic constellati on shaping (PCS) 64-quadrature amplitude modulation (64-QAM) scheme is pro posed. Then\, an active learning-aided entropy-tunable automatic modulatio n identification (AL-aided ET-AMI) scheme is demonstrated. The dynamic tim e-varying entropy is embedded in the constellation diagram and is re-extra cted at the receiver. A 10-km/ 350 ~ 550-Gb/s result is achieved over a 10 -km link within hard-decision-forward error correction (HD-FEC). For an en tropy tuning step with 0.1\, the recognition accuracy of AL-aided ET-AMI c an reach 98% with data aggregation. This scheme was subsequently extended to P2MP access networks. Our proposed scheme can provide an abundant syste m loss budget and fast graphical monitoring for flexible coherent optical transmission systems and networks.\n\nPhysical layer security is becoming an important topic in the commercial deployment of ultra-100-G optical acc ess networks. With the regulation of initial entropies\, the PCS-based opt ical link can realize a bit stream with a tunable data rate\, which facili tates mass multi-rate access. Digital signal processing (DSP) chaotic encr yption attracts more and more attention in fiber-optic networks. We first demonstrate a chaotic-encrypted transmission on a PCS-based rate-flexible CPON. The transmitted signal with various entropy is encrypted and convert ed into a cipher via mapping from PCS-64-QAM to pseudo-m-QAM format. Net r ate tuning from 211.80 Gb/s to 348.12 Gb/s with a step size of 3.408 Gbps/ pol./λ is achieved by 0.1-step entropy interval at an ROP of -15 dBm\, enc rypted by different parallel chaotic sequences. This work provides a feasi ble solution for next-generation >100-G rate-flexible and physical layer s ecurity-enhanced optical transmission.\n\nFinally\, a time division multip lexing non-orthogonal multiple access scheme is proposed for high-capacity and dense-access CPON. The scheme is experimentally demonstrated between two far-near ONUs over CPON within a single timeslot with different transm ission distances and split ratios. Different fairness indexes are defined and adopted to verify the fairness of the service from the OLT to the two far-near users. Four experiments are demonstrated with four coherent PON a pplication scenarios. A 400-Gb/s rate is achieved for two far-near users w ithin HD-FEC and flexible HD-FECs. The signal-to-interference noise ratios or bit-error rates of far-near two users are almost the same. Our propose d scheme can provide a fair service for next-generation wide-coverage cohe rent optical access systems.\n  \n DTSTART:20240613T140000Z DTEND:20240613T160000Z LOCATION:Room 603\, McConnell Engineering Building\, CA\, QC\, Montreal\, H 3A 0E9\, 3480 rue University SUMMARY:PhD defence of Zixian Wei – Coherent Optical Access Networks URL:https://www.mcgill.ca/ece/channels/event/phd-defence-zixian-wei-coheren t-optical-access-networks-357612 END:VEVENT END:VCALENDAR