如何將長期演進技術(Long Term Evolution, LTE)使用在未授權頻譜(Unlicensed Spectrum)上，近來成為各方重視的議題之一，發展中的第五代行動通訊系統(5th generation wireless systems, 5G)，也考慮了LTE在未授權頻譜上傳輸的相關規範訂定問題。
本論文會先概述LTE與建立於IEEE 802.11標準的無線網路技術WiFi (Wireless Fidelity)的相關傳輸協定，其中有LTE時頻傳輸資源介紹、IEEE 802.11標準規範介紹。還有LTE重要的技術，正交分頻多工技術(Orthogonal Frequency Division Multiplexing, OFDM)。然後本論文會導入LTE使用在原本已有WiFi的頻段上，提出一種新型LTE調度方式與WiFi共存(Co-existence)的測試平台來探討LTE與WiFi的共存特性與各項參數對其共存影響之分析。本論文主要提出的論點有：LTE調變和編碼方案(Modulation and Coding scheme, MCS)與其頻寬對共存的影響、LTE與WiFi傳輸時間比例分配的方法，稱為佔空比模式(Duty Cycling Pattern, DC Pattern)、功率控制對共存效能的影響。並且，在最後使用可靠的LTE線上監控軟體(a Reliable Online Watcher for LTE, OWL)，來驗證此研究中對LTE與WiFi共存的傳輸模式之設定與探討LTE的傳輸特性。對本篇論文總體所提出的研究，稱之為新型LTE與WiFi共存之調度探索方法。

How to use Long Term Evolution (LTE) on Unlicensed Spectrum has become one of the most important issues recently. And the fifth generation wireless communication system (5th generation wireless systems, 5G), also considered the relevant specifications for the unauthorized spectrum transmission of LTE.
This paper will first discuss transmission protocol of LTE and WiFi (a type of wireless transmission technology, also known as Wireless Fidelity) based on IEEE 802.11 standard. The discussion encompass LTE time-frequency transmission resource introduction, IEEE 802.11 standard specification introduction, and an important technique of LTE: Orthogonal Frequency Division Multiplexing (OFDM). Next, considering LTE operated on the bandwidth of Wifi, this paper introduces a new testing platform where LTE and WiFi coexist to analyze the characteristics and influences of related factors on the coexistence status. The main points of this thesis are the method of allocating the ratio of LTE and WiFi transmission time is called Duty Cycling Pattern (DC Pattern), and the effect of power control on coexistence efficiency. In the final section, we use of a Reliable Online Watcher for LTE (OWL) to verify the transmission mode settings of LTE and WiFi coexistence in this thesis and to explore the transmission characteristics of LTE. The overall research in this paper is called New LTE scheduling heuristics for co-existence with WiFi.

論文審定書 i
誌謝 ii
中文摘要 iii
Abstract iv
目錄 v
圖次 vii
表次 ix
第一章 導論 1
1.1 前言 1
1.2 研究動機 1
1.3 論文架構 2
第二章 LTE重要技術與協定 3
2.1 LTE概述 3
2.2 正交分頻多工系統之基本架構 5
2.3 LTE基本時頻傳輸資源 9
第三章 WiFi協定 11
3.1 WiFi概述 11
3.2 IEEE 802.11標準 11
3.2.1 IEEE 802.11網路架構簡介 11
3.2.2 IEEE 802.11媒體存取控制 13
第四章 實驗平台架構 17
4.1 硬體介紹 17
4.2 軟體介紹 20
4.2.1 srsLTE軟體套件介紹 20
4.2.2 OWL軟體套件介紹 22
第五章 srsLTE與WiFi於免職照頻段上共存 23
5.2 共存環境介紹 24
5.3 佔空比模式 26
第六章 實驗結果與討論 28
6.1 srsLTE與WiFi共存實驗結果分析 28
6.1.1 LTE頻寬與MCS的影響 28
6.1.2 佔空比模式之影響 31
6.1.3 功率控制影響 33
6.2 OWL驗證分析 35
6.3 驗證結果之特性實驗 40
第七章 結論 43
參考文獻 44
中英對照表 47
全名縮寫對照表 53

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