本論文提出一基於5G行動網路架構的混合式被動光網路(Hybrid PON)且具有遠端單位相互通訊(Remote Unit Interconnection)之功能。 此架構利用了波導光柵路由器(Wavelength Grating Router)的波長路由以及其週期性的自由光譜範圍(Free Spectrum Range)特性，在一架構下含蓋了多種工作模式，成功地將分時多工、分波多工以及分時分波多工被動光網路架構整合在一起，此外，透過回授路由埠，提供多樣通訊服務的同時也實現了遠端單元間通訊的功能，所連接之遠端單元可以相互通訊且能滿足低時延的應用情境需求，本文提出的網路架構概念係以能再既有被動光網路進行整合出發，以達現有光分配線網路(Optical Distribution Network)能有效再利用，預期可減少重新建置5G行動網路時所花費的成本以及時間。
模擬實驗結果顯示，在設計好的波長配置下，本論文提出的混合式被動光網路，上行、下行以及遠端單元間相互傳輸，再採前向錯誤更正(Forward Error Correction)的傳輸誤碼率需求下，皆可成功傳輸25Gb/s的NRZ訊號，並透過功率的預算，在不考慮系統餘裕下，模擬出最長的光纖總長度為40公里，驗證了此網路架構的可行性。

This research proposes a hybrid passive optical network (PON) system with remote unit (RU) inter-connection function based on 5G mobile networks. We utilize the wavelength routing and cyclic Free Spectrum Range (FSR) characteristics of the wavelength grating routing (WGR) to combine the time division multiplexing (TDM), the wavelength division multiplexing (WDM) and the time wavelength division multiplexing (TWDM) passive optical networks (PONs). With the design of the feedback ports, it also implements the RU inter-connection for the demand of the low latency usage scenario in 5G applications. The concept of the proposed architecture is to combine the existing PON system for 5G mobile network. Instead of constructing a new network, this architecture can reduce the cost and installation time.
The simulation results show that the proposed system can transmit 25Gb/s NRZ signal for downstream, upstream and RU inter-connection by wavelength allocation, and the bit error rate (BER) performance can meet the requirement of forward error correction (FEC), verifying the feasibility of the architecture. Finally, according to simulation results and the estimated power budgets, without considering system margin, the total fiber length is 40 kilometers.

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