本論文在行動通訊的雲端無線存取網路(Cloud of Radio Access Network, C-RAN)上提出一個使用非正交多重存取(Non-Orthogonal Multiple Access, NOMA)技術的兩階層配對機制(Two-Tier Paring Mechanism, TTPM)，TTPM可以透過邊緣端基頻單元(Edge Baseband Units, E-BBU)先配對部份的使用者設備(User Equipment, UE)來降低雲端基頻單元(Cloud Baseband Units, C-BBU)的負載以提升整體C-RAN的效能。另外，當兩階層C-RAN中的E-BBU 與C-BBU在進行UEs配對時，TTPM會讓要求資料速率(Request Data Rate, RDR)相近的兩個UE進行配對，因此TTPM可以更有效的使用正交頻率分割多重存取(Orthogonal Frequency Division Multiple Access, OFDMA)的資源區塊(Resource Blocks, RB)。最後，我們使用Matlab來模擬所提出的TTPM並與原始的配對機制進行效能比較，從模擬結果中，我們驗證TTPM確實可以降低C-BBU的負載、節省RB的使用、讓成功連線UE的數量明顯增加。

In this thesis, we propose a Two-Tier Paring Mechanism (TTPM) using Non-Orthogonal Multiple Access (NOMA) techniques for mobile communications in a C-RAN (Cloud Radio Access Network). To improve the overall performance of a C-RAN, TTPM can relieve the load of Cloud Baseband Units (C-BBU) by allowing the Edge Baseband Units (E-BBU) to do the pairing of partial UEs (User Equipment). In addition, in a two-tier C-RAN, the proposed TTPM can select two UEs with the nearest Request Data Rates (RDR) to do the paring, when the two UEs are under the same E-BBU or even under two different E-BBUs. As a result, the proposed TTPM can utilize the Resource Blocks (RBs) of an OFDMA frame more efficiently. Finally, we use Matlab to simulate the proposed TTPM and compare its performance with the original pairing mechanism. From the simulation results, we validate that the proposed TTPM can indeed reduce the load of C-BBU, save large amount of RBs, and significantly increase the number of successfully connected UEs.

論文審定書 i
致謝 ii
摘要 iii
Abstract iv
目錄 v
圖目錄 vii
表目錄 ix
第一章 緒論 1
1.1研究動機 1
1.2研究方法 2
1.3章節介紹 3
第二章 C-RAN架構下的NOMA配對機制 4
2.1 T-RAN與C-RAN 4
2.1.1 T-RAN 5
2.1.2 C-RAN 8
2.2 UE連線的訊號雜訊比 9
2.3 UE的多工技術 10
2.3.1 SC-FDMA 10
2.3.2 OFDMA 11
2.3.3 NOMA 12
2.4 相關研究與文獻的比較 16
第三章 C-RAN的兩階層配對機制 18
3.1 兩階層的C-RAN架構 18
3.2 兩階層NOMA配對機制 20
3.2.1 UE的連線狀態轉換 21
3.2.2 UINP Header 23
3.2.3 Edge BBU的Process 25
3.2.4 Cloud BBU的Process 30
第四章 模擬與結果討論 32
4.1 C-RAN的模擬拓樸 32
4.1.1 UE在模擬中的分佈拓樸 33
4.1.2 UE的虛擬碼 36
4.1.3 GeneratePacket函式 37
4.1.4 E-BBU的虛擬碼 42
4.1.5 C-BBU的虛擬碼 45
4.2 模擬結果與分析 47
4.2.1 UE在三個區域的分佈比例為1:1:1 48
4.2.2 UE改變三個區域分佈比例 55
第五章 結論與未來工作 59
5.1結論 59
5.2未來工作 60
Reference 61
Acronyms 65
Index 67

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