第五代行動通訊非獨立組網下可靠度之提升與測量

Reliability Enhancement and Measurement in 5G NSA Environment

林達生(Ta-Sheng Lin)

指導教授 ： 魏宏宇

國立臺灣大學/電機資訊學院/電機工程學研究所/碩士(2022年)

https://doi.org/10.6342/NTU202202489

摘要

目前所發展的第五代行動通訊非獨立組網 (Fifth-Generation Non-Standalone Architecture, 5G NSA) 可以為用戶提供更高數據速率的服務。不過，對於一些特殊的應用，例如列車控制訊息的傳送，可靠性和延遲才是關鍵的性能指標。本研究旨在提高鐵路環境下的相關性能指標。我們首先進行測量，找出鐵路環境中與性能相關的環境因素。我們分析鐵路環境下所蒐集的測量數據，並驗證了位置和換手都與異常的表現相關，例如封包丟失以及過長的延遲。我們還觀察到有些換手事件是不必要的。透過這些發現，我們提出了一個可以減少換手和無線連結失效 (Radio Link Failure, RLF) 對可靠度的影響並顯著提高性能的系統。我們還提出了一個可以為系統快速找到最佳設定的流程。這項研究也也透過實際的實驗結果驗證本研究所提出的系統可以顯著提高性能。

關鍵字

第五代行動通訊非獨立組網 ； 網路測量 ； 鐵路通訊 ； 換手 ； 通訊可靠度 ； 封包傳送時延 ； 頻帶鎖定 ； 多路徑傳輸

並列摘要

The current non-standalone (NSA) Fifth-Generation (5G) networks can give users higher data rate services. However, for some vertical market applications, such as the railway environment development, reliability and latency other than data rate are key performance metrics. This study aims to enhance the metrics under the railway environment. We first have measurements to find out the performance factors related to performance in the rail environment. We analyzed measurement data under the metro rail environment and verified that both location and handovers (HOs) are associated with unsatisfactory performance, such as packet losses and excessive latency. We also observed that some HO events are unnecessary. With these insights, we propose a system that can reduce the impact of the HOs and RLFs and largely enhance the performance. We also propose a procedure to find the best configuration for the system. This work also shows experimental results showing that the proposed system can significantly enhance performance.

並列關鍵字

5G NSA ； Network Measurement ； Railway Communications ； Handover ； Communications Reliability ； Packet Delivery Latency ； Band Locking ； Multipath

參考文獻

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