本論文針對無線區域網路(Wireless Local Area Network ,WLANs)中的Orthogonal Frequency Division Multiple Access (OFDMA) 產生的資料單元(Resource Units, RU)分配問題，提出了有效的解決方案。在下一代IEEE 802.11be 協議為OFDMA機制引入了新的資料型態，稱為Multiple Resource Units(MRU)，該型態支持將多個RU分配給單個使用者，使得頻寬利用率提升，RU分配的模式變得更加靈活。但是該資料型態有著嚴格的位置限制，使得分配MRU變成一個難題。我們發現RU在未經分配的狀態下，很可能會導致頻寬浪費的問題，這會使得總體吞吐量下降。在本文所提出的方案中不僅透過MRU分配策略改善了回合傳輸時間，還針對MRU擺放問題進行了優化，考慮不同的MRU組合為效能帶來的影響。最終根據模擬結果，本文所提的方案在傳輸時間、吞吐量上都優於其他方案。

This paper addresses the issue of Resource Unit (RU) allocation in Wireless Local Area Networks (WLANs) using Orthogonal Frequency Division Multiple Access (OFDMA). In the next-generation IEEE 802.11be standard, a new data type called Multiple Resource Units (MRUs) is introduced for the OFDMA mechanism. MRUs allow multiple RUs to be allocated to a single user, enhancing bandwidth utilization and providing more flexible RU allocation patterns. However, MRUs come with strict placement restrictions, making their allocation a challenging problem. We found that unallocated RUs can lead to bandwidth waste, which in turn decreases overall throughput. The solution proposed in this paper not only improves transmission time through an optimized MRU allocation strategy but also addresses the MRU placement issue, considering the impact of different MRU combinations on performance. Simulation results demonstrate that the proposed solution outperforms other schemes in terms of transmission time and throughput.

目錄
第1章 介紹	1
第2章 背景知識	8
2.1 MRU	8
2.2 問題表述	11
第3章 最小化最大傳輸時間模型建模	12
第4章 回合時間最小化之MRU分配方案	16
4.1 理論基礎	16
4.2回合時間最小化之MRU分配方案	18
第5章 效能評估	22
5.1實驗場景及參數設定	22
5.2實驗結果	25
第6章 結論	29
參考文獻         30

圖目錄

圖一、OFDMA機制將多個RU分配給不同的STA	3
圖二、20MHz的RU分配圖	4
圖三、OFDMA下行傳輸	5
圖四、OFDMA上行傳輸	6
圖五、MRU與 上一代RU差異	9
圖六、52+26tone MRU 在20MHz的位置分配規[10]	10
圖七、484+242 tone MRU在80MHz的位置分配規則[10]	10
圖八、未進行RU分配示意圖	11
圖九、每個傳輸回合的時序圖	14
圖十、4個STAs運行在20MHz的時序圖與RU分配圖	16
圖十一、縮短回合時間示意圖	17
圖十二、 使用RU分配方案後的時序圖和RU分配圖	18
圖十三、MRU分配方案決策圖	19
圖十四、MRU的擺放位置分配圖	20
圖十五、1個AP和20個STAs場景圖	22
圖十六、比較兩種方案在一回合內的傳輸時間	25
圖十七、網路總體效能比較	26
圖十八、各個STAs在不同方案的吞吐量比較	27
圖十九、三種方案的總吞吐量比較	28

表目錄

表一、EDCA與DCF的各項參數差異	2
表二、26-tone RU 在不同調制編碼方案的速率(Mbps)	12
表三、MRU/RU所等同的26-tone RU數量表	13
表四、MRU分配方案輸出結果	20
表五、模擬參數	23
表六、流量類別參數	23

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