可擴充下行軟體實體層於雲端無線網路架構

Scalable Downlink of Soft PHY in a Cloud-RAN

沈志穎(Chih-Ying Shen)

指導教授 ： 許騰尹

國立交通大學/資訊學院/資訊科學與工程研究所/碩士(2020年)

摘要

由於行動通訊網路傳輸量需求日益增加，使得調整基地台的布建策略成為目前相當重要的挑戰之一，其中集中式處理資料概念將是第五代行動通訊網路(5th Generation Mobile Networks, 5G)的關鍵技術。相較目前商用基地台之硬體設計(Hard PHY)，軟體化實體層(Soft PHY)更能彈性修改以因應5G規格之變動。
然而，相較於以往PHY Layer的硬體設計，Soft PHY在運算效率上仍有優化的空間。本研究主要提出可擴充下行Soft PHY，目的是為了因應未來Cloud-RAN技術，需要軟體化與虛擬化至多台伺服器上運行，以突破Soft PHY在運算時受單一伺服器硬體資源的限制。本論文將著重於Soft PHY程式的模組化(Modularization)，並以分散式運算架構的開發來驗證其正確性，使Soft PHY能夠擁有更高的可擴充性來彈性使用額外的硬體資源，提供更佳的運算能力。
提出分散式計算架構，除了提高整體基地台的負載量之外，更重要的是為了驗證本論文所提出的Scalable Soft PHY是否有獨立運算、可擴充、易於分割做開發的能力，最終通過實驗比較也證明相較於原版Soft PHY，我們基地台提供的傳輸速率及真實負載量都有明顯提升。

關鍵字

第五代行動通訊網路 ； 分散式計算架構 ； 可擴充的軟體實體層 ； 光纖傳輸

並列摘要

Due to the increasing demand for mobile communication network transmission, adjusting the deployment strategy of baseband unit has become one of the most important challenges. The concept of centralized data processing will be the key technologies of 5th Generation Mobile Networks (5G). Compared to the current hardware design of commercial baseband unit (Hard PHY), the software-defined physical layer (Soft PHY) can be more flexibly modified to respond to 5G specifications updating.
However, Soft PHY still has lots of space to improve. In this paper, we propose scalable downlink of soft PHY for virtualizing the computation to multiple servers in Cloud-RAN. In order to break the limitation of computing resources on single server. To enhance the scalability of Soft PHY that can lead to high computational capacity, this paper focuses on the modularization of Soft PHY and verify the correctness using distributed computing architecture of Soft PHY.
Proposing a distributed computing architecture, in addition to increasing the load of the overall baseband unit, it is more important to verify whether the Scalable Soft PHY proposed in this paper has the ability to independently calculate, scalability, and easily partition for development. Finally, it also proves that compared to the original Soft PHY, the transmission rate and real load provided by our baseband unit have been significantly improved.

並列關鍵字

5G ； OAI ； Distributed Computing Architecture ； Scalable Soft PHY ； Fiber-optic Communication

參考文獻

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