在IEEE 802.11無線區域網路中，設計一改善非對稱流量傳輸之頻道竊用全雙工媒體存取控制協定

A Channel-Stealing Full-Duplex MAC Protocol for Asymmetric Traffic in IEEE 802.11 WLANs

曹傑閔(Jie-Min Cao)

指導教授 ： 石貴平

淡江大學/工學院/資訊工程學系碩士班/碩士(2018年)

https://doi.org/10.6846/TKU.2018.00214

摘要

本論文針對同頻全雙工無線區域網路(In-Band Full Duplex Wireless LANs, IBFD WLANs)中，非對稱傳輸下所造成的效能下降問題，提出一有效的解決策略。隨著天線設計與訊號處理的新進展，使得使用者能透過相同的頻道同時發送與接收資料，該技術稱之為同頻全雙工。然而實體層的進步，需要搭配有效的IBFD媒體存取控制(MAC)協定以達到更佳的效益。另外，由於上傳與下載的傳輸流量通常都不相同，使得在進行IBFD傳輸時，容易產生頻道閒置的浪費。因此本論文提出一頻道竊用的媒體存取控制協定，簡稱為Channel-Stealing Full Duplex (CSFD) MAC，以解決上傳-下載傳輸鏈路的非對稱傳輸問題。CSFD的特色是竊用因非對稱傳輸所產生的頻道閒置時間，增加傳輸機會，以提昇非對稱傳輸之效能。本論文透過OMNET++模擬器與其他相關研究進行比較，結果顯示CSFD在不同的非對稱傳輸場景中，效能與傳輸延遲都優於半雙工與相關研究，且較適用於未來的IBFD WLANs。

關鍵字

IEEE 802.11 ； 同頻全雙工 ； 非對稱傳輸 ； OMNET++ ； WLANs

並列摘要

This paper proposes an effective solution to the performance degradation caused by asymmetric transmission in In-Band Full-Duplex Wireless LANs (IBFD WLANs). Along with antenna design and signal processing advancements, users can simultaneously send and receive data through the same channel, which is called IBFD transmission. However, advancements in the physical layer, efficient IBFD Medium Access Control(MAC) protocol is required to achieve optimum benefit from this latest technology. Moreover, since transmission traffic of uplink and downlink is usually different, so IBFD transmission is easy to generate waste of channel idleness. Therefore, in this paper, a Channel-Stealing Full Duplex (CSFD) MAC is proposed to solve the asymmetric transmission problem in the uplink-downlink transmission. The main feature of CSFD is increasing transmission opportunities by stealing channel idle time due to asymmetric trans-mission to improve the performance of the asymmetric transmission. CSFD compares with the related research (A-duplex) by OMNET++ simulator. The simulation results suggest that the throughput and transmission delay of CSFD outperforms traditional half-duplex and A-Duplex in different asymmetric transmission scenarios, which can be used for future FD WLANs.

並列關鍵字

IEEE 802.11 ； In-Band Full-Duplex ； Asymmetric Traffic ； OMNET++ ； WLANs

參考文獻

參考資料

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