行動式的IEEE 802.16e (WiMAX) 環境，已被視為一個具有前瞻性的無線視訊群播技術，諸如行動數位電視的視訊串流服務，可在此環境中被支援。為了支援如此消耗能源的服務，我們需要在此環境中運用節能機制 (睡眠模式)。睡眠模式可以將基地台與Mobile Station (MS) 間的一些未傳輸資料的連線 (connection)，進入睡眠狀態。一旦所有連線都進入睡眠模式，MS將可進入省電狀態，使得MS的使用壽命更長。由於在標準文件中，關於即時性連線的睡眠模式運作，並沒有定義出:如何使一條處於正常模式的連線進入和離開睡眠模式，而且現有睡眠模式的運作可以更有節能效率和增進Quality of Service (QoS)。因此，我們實驗室所提出的雙計時器機制 (Two-Timer Mechanism)，可以使即時性連線進入和離開睡眠模式，並且使睡眠模式的節能效率和QoS更好。本篇論文首先分析出一個大致的WiMAX MAC平台架構，再設計與實作我們所提出的雙計時器機制於其中。主要實作位置在WiMAX的基地台的MAC層，並且使用資策會所提供的C語言平台。由驗證部份可以看出，我們所送出的MOB-SLP-RSP封包內容符合標準文件定義，將可以使可支援睡眠模式的MS的即時性連線進入睡眠模式。

The mobile IEEE 802.16e (WiMAX) environment has been considered a promoting wireless video multicasting technology. For example, mobile digital TV, which is one of video streaming service, can be supported in this environment. In order to support energy-consuming service like this, we need to operate some energy-saving mechanisms in the environment. In the IEEE 802.16e standard, some energy-saving mechanisms called “sleep mode operations” have been defined. Sleep mode operations can make connections between base station (BS) and mobile station (MS) enter sleep mode. While all of the connections enter sleep mode, MS can enter an energy-saving state. But in the standard, for real-time connections, it does not mention that how to switch a connection between awake mode and sleep mode. And the sleep mode operation for real-time connections can be more efficient about energy-saving and the Quality of Service (QoS) can be higher. So we have proposed “Two-Timer Mechanism” which can make real-time connections switch between awake mode and sleep mode, upgrade the efficiency of sleep mode operation, and improve the QoS. In this thesis, after a general structure of WiMAX MAC layer is analyzed, our Two-Timer Mechanism is designed and implemented in media access control (MAC) layer of WiMAX BS on the C platform provided by Institute for Information Industry (III). The conformance testing shows that MOB-SLP-RSPs conform to the standard. So it can work sleep mode operations on real-time connections successfully.

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