在LTE網路環境中，基於MOS之即時性流量排程機制

MOS-based Real-Time Traffic Scheduling in LTE Network

許翰嘉(Han-Chia Hsu)

指導教授 ： 楊峻權

國立暨南國際大學/科技學院/資訊工程學系/碩士(2020年)

https://doi.org/10.6837/ncnu202000021

摘要

隨著科技的快速發展，智慧型裝置的普及化，使用者對於網路的需求提高，長程演進技術 (Long Term Evolution, LTE) 由第三代合作夥伴計畫 (3rd Generation Partnership Project, 3GPP) 所開發，是目前4G/5G標準的一種網路接取技術。LTE的網路架構中，介紹行動用戶 (User Equipment, UE) 如何透過無線資源與基地台(Evolved NodeB, eNB)進行連線建立並連至核心網路 (Evolved Packet Core，EPC)。
LTE在MAC層具有Quality of Service (QoS) 的分層架構概念，提供多媒體服務和高頻寬數據傳輸使用，根據資料流量的不同而劃分多種QoS等級。大部分排程演算法探討如何利用有限的無線資源條件下，做出最佳的資源分配方式，並同時在公平性、系統吞吐量之間取得平衡，一直是目前排程研究的討論議題。然而這些相關的排程演算法中大多並不考慮體驗品質 (Quality of Experience, QoE)，體驗品質可以透過E-Model來計算使用者的平均意見分數 (Mean Opinion Score, MOS)，因此本文提出基於MOS、Head of Line (HOL)、Delay Budget、Proportional Fair (PF)的排程演算法，目標為提升使用者的MOS，在模擬結果的部份，本文所提出的方法在分配無線資源時並不會偏袒特定應用，並且能夠減少Delay及Packet Loss Rate (PLR)，藉以提升MOS，在提升MOS的同時，也能維持不錯的公平性及吞吐量。

關鍵字

長程演進技術 ； 即時性資料流量 ； 服務品質 ； 體驗品質 ； 平均意見分數 ； 公平性 ； 資源分配 ； 排程

並列摘要

With the rapid development of science and technology, the popularization of smart devices and the increasing demand of users for the network, Long Term Evolution (LTE) was developed by the 3rd Generation Partnership Project (3GPP), which is a network access technology of the current 4G/5G standard. In the network architecture of LTE, it introduces how the User Equipment (UE) can establish and connect to the Evolved Packet Core (EPC) by means of a wireless resource.
LTE has the concept of level architecture of Quality of Service (QoS) on the MAC layer, providing multimedia services and the use of high-frequency and wide data transmission, and classifying various QoS levels according to different data flows. Most scheduling algorithms discuss how to make the best resource allocation under the condition of limited wireless resources, and achieve the balance between fairness and system throughput at the same time. In addition, Quality of Experience (QoE) can be used to calculate user's Mean Opinion Score (MOS) through E-Model. However, most of these relevant scheduling algorithms do not consider QoE. Therefore, this thesis proposes a scheduling algorithm based on MOS, Head of Line (HOL), Delay Budget and Proportional Fair (PF), aiming at improving user's MOS. As illustrated in simulation results, the proposed mechanisms do not favor specific applications when allocating wireless resources, and can reduce Delay and Packet Loss Rate, so as to improve MOS. Moreover, the proposed mechanisms not only do improve MOS, but also maintain good fairness and throughput.

並列關鍵字

LTE ； Real-Time Traffic ； Quality of Service ； Quality of Experience ； Mean Opinion Score ； Fairness ； Resource Allocation ； Scheduling

參考文獻

[1] S. Sesia, I. Toufik and M.P.J. Baker, LTE-The UMTS Long Term Evolution: From Theory to Practice, Wiley, April. 2009.

[2] 3GPP, “Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN),” TS 36.300, v10.3.0, March. 2011.

[3] 3GPP, “Radio Access Network; UTRAN Overall Description,” Tech. spec. TS 25.401, v. 10.2.0, June. 2011.

[4] 3GPP, “Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN),” TS 36.300, v.8.5.0, March. 2008.

[5] 3GPP, “Radio Access Network; E-UTRA and E-UTRAN Overall Description,” Tech. spec. TS 36.300, v. 11.1.0, March. 2012.