隨著行動通訊技術的不斷演進，以及各種新興智慧行動終端的出現，由國際電聯無線電通信部門所規範之下世代行動通訊網路技術（通常被稱為“4G”）預期能為許多行動數據應用服務提供最佳的解決方案。而電機電子工程師學會亦在遵循此規範下，提出了相對應的標準，稱為IEEE 802.16m空中接口標準。此外，由於下世代之行動通訊網路技術皆需支援“移動性”，亦即在行動裝置移動的過程中持續的提供用戶高品質且穩定的服務，也使得如何提升其電源裝置的蓄電能力受到相當的注目與挑戰。因此，IEEE 802.16m標準延伸了其上一代標準之概念，提出了更加有效率的省能機制（該省能機制包含了睡眠模式以及閒置模式），以期能有效的延長行動終端重新充電前的使用時間。另一方面，現今常見的數據應用服務，包含如WWW、電子郵件、多媒體影音、語音視訊電話…等，皆具有叢集（burstiness）的特性，此特性使得這些服務的訊務模型，不管在檔案封包大小的分佈或者封包間、叢集間及段落間的分佈，皆不再適用以往用於傳統語音訊務的卜瓦松與指數分佈。
在本研究中，我們建構了一個新的半馬可夫程序模擬IEEE 802.16m標準整體的省電機制，並檢驗此機制在面對不同訊務時（包含ETSI模型、WWW、及即時視訊），所反應的省能效率以及喚醒延遲。研究結果顯示，我們所建構的半馬可夫程序能完整執行IEEE802.16標準的省電機制運作，並藉由導入各種不同的訊務模型，我們能在有效提高省能效率的基礎下，獲得針對各種訊務最適當的初始參數設置。

The fourth generation (4G) mobile network technology is expected to provide optimal wireless network in response to the flourish of many data application services. Aiming to meet the requirements of 4G defined by the ITU-R, one of the standard bodies, IEEE, has paid so much effort into developing its own option called IEEE 802.16m air interface standard. Moreover, since this standard has been also proposed to support mobility so that mobile subscriber stations (MSSs) are capable to move during the service time, the lifetime of these MSSs will then be severely constrained by their energy-limited battery. Due to this fact, IEEE 802.16m standard, therefore, adopts its own power-saving mechanism (including “Sleep mode” and “Idle mode”). Besides, modern packet data traffics, such as WWW, E-mail, streaming multimedia and Video telephony, commonly seen in today’s wireless broadband networks, show the characteristics of burstiness. This leads to the consequences of heavy-tailed distributions in both file size and inter-arrival times between packets, bursts or sessions, and also causes the failure of Poisson modeling.
In this research, we first propose a novel model based on semi-Markov process to formulae the overall power-saving mechanism adopted by IEEE 802.16m standard and then examine power-saving efficiency and wake-up delay under different traffic models including ETSI, WWW and NRT-video. The results show that our proposed model can well perform the whole operation of IEEE 802.16m’s power-saving mechanism. Also, by applying different traffic models, we can obtain the most proper initial parameter settings for IEEE 802.16m’s power-saving mechanism to maximize the power efficiency.

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