在無線網路架構中的資源限制較有線網路大，在無線網路中的排程設計與網路資源管理和通訊排程有密切的關聯，妥善分配資源的排程方式可以達到提升系統效能的目的。
    IEEE 802.16j是針對原有的IEEE 802.16標準加入了中繼台結構，目的為對處在涵蓋範圍邊緣的行動台或是處在基地台死角的行動台提供服務，或是在基地台布建不易的地方使用多躍式傳遞訊息的技術。而此新結構的加入，使得原本的排程方式必須做出改變。
    本研究提出一個分散式排程的機制，此機制適用於非穿透式基地台的網路系統中，目標為達到WiMAX對服務品質的保障，此外還欲加強對於即時通訊服務類型的服務品質。
　　經由模擬實驗結果證明，本研究所提出的排程演算法跟據代表性的文獻比較之下，對於即時通訊的連線而言，在封包平均延遲時間及封包丟棄率上有較佳的表現，符合本研究欲提升即時通訊服務品質之目的。

Radio resource management issue in wireless network is much stricter than in backbone network. The scheduling scheme in wireless network is close to resource management, and the main purpose of scheduling is for QoS guarantee.
    In IEEE 802.16j, the new specification for relay stations which provide service for the mobile stations which are in a blind spot or infected by shadow fading. A relay station is easier to construct when the backbone network is limited for some circumstances. With the new architecture of relay stations, we have more challenges to the scheduling issue.
    In our thesis, we are going to investigate a distributed scheduling scheme for WiMAX system with non-transparent relay stations. Our proposed scheme could provide QoS guarantee and additionally enhance the QoS for real-time service. 
    Simulation results show that our proposed scheduling scheme can reduce the packet average delay time and the packet average drop rate for real time service compared with other representative researches. Therefore, our research can guarantee the QoS of real time service connections.

目錄	III
圖目錄	VI
表目錄	VII
公式目錄	VIII
第一章	緒論	1
1.1 導論	1
1.2 研究動機與目標	2
1.3 研究方法簡介	5
1.4 論文架構	6
第二章	相關技術與研究	8
2.1 IEEE 802.16技術介紹	8
2.1.1 前言	8
2.1.2 IEEE 802.16標準的特性	10
2.1.3 媒體存取控制子層(MAC Layer)介紹	12
2.1.4 IEEE 802.16標準之QoS介紹	14
2.2 多躍中繼技術介紹	16
2.2.1 前言	16
2.2.2 中繼台(Relay Station, RS)介紹	17
2.2.2.1 中繼台提供的優勢	17
2.2.2.2 中繼台的種類	19
2.3 排程問題之相關研究	25
2.3.1 前言	25
2.3.2 排程模式介紹	26
2.3.3 相關文獻介紹	27
2.3.4 小結	29
第三章	即時通訊服務為主的可適性分散式排程機制	31
3.1 前言	31
3.2 網路環境介紹	32
3.3 系統整體機制概述	33
3.4 優先權的分派(Priority Assignment)	38
3.4.1 前言	38
3.4.2 服務類型的排序(Service Type Ranking)	39
3.4.3 優先權的調整(Priority Adjustment)	40
3.4.3.1 優先權的提升(Priority Promotion)	41
3.4.3.2 優先權的下降(Priority Diminution)	47
3.4.4 小結	47
3.5 資源的分配(Resource Allocation)	48
3.5.1 前言	48
3.5.2 頻寬需求之計算(Bandwidth Requirement Calculation)	49
3.5.3 頻寬分配(Bandwidth Allocation)	55
3.5.4 小結	59
3.6 優先預留頻寬的調整(Preserved Bandwidth Adjustment)	59
3.6.1 前言	59
3.6.2 預留頻寬之優點	60
3.6.3 頻寬使用情況報告(Bandwidth Status Report)	61
3.6.4 預留頻寬的重新分配(Preserved Bandwidth Re-Allocation)	62
3.6.5 小結	63
第四章	模擬結果探討	64
4.1 前言	64
4.2 模擬環境與參數	64
4.3 模擬數據與比較分析	67
第五章	結論與未來方向	71
5.1 結論	71
5.2 未來研究方向	71
參考文獻	73
附錄—英文論文	77

圖 1　　基地台與中繼台涵蓋範圍示意圖	18
圖 2　　框架前導訊號示意圖	20
圖 3　　基地台與穿透式中繼台之框架結構圖	22
圖 4　　基地台與非穿透式中繼台之框架結構圖	24
圖 5　　DFPQ排程機制之架構	29
圖 6　　分時多工(TDD)技術示意圖U	33
圖 7　　RTDS架構圖	37
圖 8　　優先權分派之架構圖	39
圖 9　　調整後各服務類型之優先權區間圖	41
圖 10　封包抵達與延遲時間圖	42
圖 11　資源分配架構圖	49
圖 12　模擬環境圖	65
圖 13　即時通訊類別封包之平均延遲時間	67
圖 14　封包延遲與系統負載度之關係圖	69
圖 15　封包丟棄率與系統負載度之關係圖	70

表 1  中繼台功能與排程方式差異表	27
表 2  IEEE 802.16標準中之QoS相關參數	35
表 3  各服務類型之優先權初始值表	40
表 4  模擬參數表	66
 
公式(1) 封包等待時間	43
公式(2) 封包剩餘停留時間	43
公式(3) 封包延遲容忍度	44
公式(4) 封包延遲容忍度之正規化	44
公式(5) 封包過期時間判斷	45
公式(6) 封包緊急度	46
公式(7) 封包緊急度之正規化	47
公式(8) 優先權下降值	47
公式(9) 連線之頻寬需求上限	50
公式(10) 連線之頻寬需求下限	51
公式(11) UGS頻寬需求上限	52
公式(12) UGS頻寬需求下限	52
公式(13) ertPS頻寬需求上限	52
公式(14) ertPS頻寬需求下限	52
公式(15) rtPS頻寬需求上限	53
公式(16) rtPS頻寬需求下限	53
公式(17) nrtPS頻寬需求上限	53
公式(18) nrtPS頻寬需求下限	53
公式(19) BE頻寬需求上限	54
公式(20) BE頻寬需求下限	54
公式(21) 總頻寬需求上限	54
公式(22) 總頻寬需求下限	55
公式(23) 系統頻寬與總需求上限比較	55
公式(24) 系統頻寬與總需求下限比較	55
公式(25) 計算系統剩餘頻寬-1	56
公式(26) 計算系統剩餘頻寬-2	57
公式(27) 判斷排程工作是否結束	58

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