為了實現無線都會型區域網路(WMAN)之多樣式行動服務，IEEE 802.16e標準被制訂以應用於支援固定用戶站 (Fixed Station)及行動用戶站 (Mobile Station)的寬頻無線存取系統 (Broadband Wireless Acess Systems)。由於行動用戶站都是以電池當做能量來源，因此能源節省在IEEE 802.16e成為非常重要的研究議題，所以IEEE 802.16e標準訂定三種不同的能源節省類型並以啟用睡眠模式的方式來達到節能效果。然而在其能源節省類型I之標準睡眠模式運作中，行動用戶站對於不同的訊務樣式 (Traffic Pattern)都使用固定的睡眠方式，亦即以最小睡眠區間進入睡眠模式，再以兩倍增長的方法增加其睡眠區間長度直至最大睡眠區間，因此在較低封包抵達速率的情況下，行動用戶站會浪費許多能源且遭遇長的封包延遲。為了改善此問題，本論文提出了三個預測式動態睡眠時間規劃節能機制，
亦即PDSTP-CL、 PDSTP-ED與PDSTP-LD，此三種節能機制利用預測之封包間隔時間動態地規劃行動用戶站之睡眠模式，讓行動用戶站可於適當的時間清醒以服務封包，而在其它時間中則儘量地處於睡眠狀態中，利用此方式，使得封包抵達的時候能快速地被服務，並且讓行動用戶站於等待封包抵達的過程中減少能源浪費，以達到同時改善封包延遲與能源節省的效果。透過模擬比較，我們所提之PDSTP-CL節能機制表現優於PDSTP-ED與PDSTP-LD節能機制，且於能源節省及封包延遲上PDSTP-CL都能表現優於IEEE 802.16e之標準機制以及其他文獻中的相關機制。

In order to realize various mobile services for the wireless metropolitan area network (WMAN), the IEEE 802.16e standard was proposed for the broadband wireless access system supporting the fixed stations and mobile stations (MSs).
Because MSs are powered by batteries, energy conservation becomes an extremely important research issue in IEEE 802.16e which defines three different types of power saving class and reaches the energy conservation goal by adopting the sleep mode. However, MSs, which adopt the standard sleep mode operation of power saving class of type I, may waste a lot of energy and suffer long packet delay when the traffic arrival rate is low since the same sleep mode is used for different traffic patterns. That is, MSs enter the sleep mode with the minimal sleep period and then double the sleep period as the sleep cycle increases until the maximal sleep period is reached. To solve this problem, we propose three predictive and dynamic sleep time planning (PDSTP) power saving mechanisms in this thesis, i.e., PDSTP-CL, PDSTP-ED, and PDSTP-LD, to dynamically plan the sleep mode for MSs according to the predicted inter-packet arrival time, and to let MSs wake up to receive packets at an appropriate time instant while sleep as much as possible before this time instant. By using this way, queued packets can be served faster and energy consumption can be reduced, so that the packet delay can be reduced and the energy efficiency can be improved simultaneously. Through simulations, we show that PDSTP-CL outperforms PDSTP-ED, PDSTP-LD, the standard mechanism of IEEE 802.16e, and other related schemes in the literature in terms of energy efficiency and packet delay.

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