IEEE 802.11ax 媒體存取控制層協定之設計

Abstract

為了能夠從基礎上提高無線區域網路(WLAN) 之802.11 的效能，IEEE 802.11ax 已經被提出來實現下一代無線區域網路。針對裝置密度高及壅塞的網路環境，802.11ax 要能夠提供有效率的通道共用機制來達到應用層所需要提供良好服務品質的服務質量(QoS) 和使用者經驗。因此媒體存取控制層的協定扮演很重要的角色。不同於過去的單一使用者傳輸，新的實體層(PHY layer) 能夠支援多個使用者同時傳輸，所以媒體存取控制層的協定就要重新的規劃。在這篇論文中，我們指出了一些802.11ax 媒體存取控制層協定的設計議題，接著根據現有的標準，我們針對隨機擷取、優先權的支援及重疊的基本服務單元(OBSS)等議題，提出研究動機、研究困難及設計的原則。接著最後，為了減緩LTE-LAA 對802.11ax 服務質量的影響，我們提出解決方案。

To seek for fundamental improvement of 802.11, a new effort knownas IEEE 802.11ax has been approved to deliver next generation wireless localarea networks (WLAN) technologies in dense environments. In WLAN,to enable efficient channel sharing while providing quality of service (QoS)and high user experience for multimedia applications, medium access control(MAC) protocol is the crucial component.To catch up with the new physicallayer, featuring simultaneous multi-user transmission, new MAC functionsneed proposing. In this thesis, we point out several design issues for MACprotocol. Based on the draft recently issued, we present and discuss some issues,e.g., the design principles of random access, priority support, and overlappingbasic service set (OBSS) management. Furthermore, to relieve theimpact LTE Licensed-Assisted Access (LTE-LAA) brought on QoS provisioningin IEEE 802.11ax, the coexistent problem is addressed in the end ofthis thesis.