隨著科技的日漸蓬勃，無線通訊技術快速的發展，手持裝置、膝上型電腦等等眾多的行動裝置快速的普及。行動裝置開始能提供高速數據傳輸的服務，如即時多媒體串流、網頁瀏覽、語音通話等等。而高數據傳輸勢必伴隨著高能源消耗的問題，行動裝置能源是有限的，因此如何減少行動裝置上能源的消耗並同時提供高速數據傳輸的服務成為一個很重要的挑戰。
　　為了改善能源消耗的問題，在長期演進技術中提出了不連續接收省電機制，以定期關閉射頻模組來達到節省能源的目的。然而關閉射頻模組會造成封包傳送的延遲，在舊有的封包排程機制並沒有考慮到此點，而導致系統無法正確的分配無線資源，使有緊急需求的使用者無法得到資源的分配，也因此累積過多的延遲而使封包過期，最後影響的便是無法滿足使用者的服務品質需求。
　　因此本論文以不連續接收省電機制造成的延遲時間和服務品質作為考量來改進傳統的長期演進技術下行封包排程機制，使其可以正確的依據緊急性分配無線資源，同時可以滿足使用者的服務品質，且最後能達到在行動裝置上節省能源的目的。
　　模擬結果顯示，我們提出的方法相較其他的排程機制，可以有效的減少封包遺失率，並提高能源節省的效能。

The development of the technology, especially the rise of wireless communication technology, has made many mobile devices such as handheld devices and laptops popular. There are many high-speed transmission services on mobile devices such as real-time multimedia streaming transmission, website browsing, VoIP and so on. For the requirement of the high-speed transmission, it occurs the problem of high power consumption. At the same time, due to the finite power of mobile devices, it is a challenge to reduce power consumption and provide a high-quality services on mobile devices. To improve the issue on consuming electric power, there is a method called discontinuous reception mechanism (DRX) in long term evolution (LTE), which can achieve the energy saving by shutting down the radio frequency module regularly. However, it would cause a delay on transmitting packets when radio frequency module is closed. In many previous packets scheduling mechanisms, do not consider the extra delay and we cannot distribute the resources correctly to the users when having emergency. An excessive delay happened, and that would cause packets expired. If it happens, it would not meet the demand on the quality of services (QOS) for users. In this thesis, we present a DRX-Aware LTE downlink scheduling mechanism for real- time traffic. Our mechanism can allocate resources to those packets which carry emergent messages. Meanwhile, it can satisfy the QOS for users and achieve the purpose of saving energy. The simulations are conducted by NS-3 to analyze the performance of the proposed method. And the simulation results show that the proposed method can effectively reduce the power consumption and packet loss rate.

目錄
學位論文審定書 i
論文公開授權書 ii
論文摘要 iii
Abstract iv
目錄 v
圖目錄 vii
表目錄 ix
第一章 導論 1
1.1 前言 1
1.2 研究動機 3
1.3 論文架構 4
第二章 相關背景與研究 5
2.1 3GPP長期演進技術(LTE)簡介 5
2.1.1 LTE基本系統架構 6
2.1.2 LTE無線存取技術 9
2.1.3 無線資源控制層(Radio Resource Control) 15
2.1.4 無線資源管理(Radio Resource Management) 20
2.2 不連續接收省電模式(Discontinuous reception) 22
2.2.1 DRX機制介紹 22
2.2.2 DRX參數介紹 23
2.2.3 RRC狀態下的DRX 26
2.3 相關論文 28
第三章 研究方法 34
3.1 系統架構 34
3.2 封包排程機制 36
3.3 DRX start offset decision 40
3.4 資源分配機制 44
第四章 效能與分析 45
4.1 模擬環境與參數設定 45
4.2 模擬結果與效能分析 47
第五章 結論 56
參考文獻 57

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