IEEE 802.16是目前最受矚目的長距離無線網路協定之一，主要目的為在都會區提供容易架設且高效率及高頻寬的網路，為了在複雜的環境之中，提供客戶端一個高效率的服務，IEEE 802.16中制定了詳細的QoS架構，針對不同的需求而有等級及優先權的排列，但在協定之中並未十分仔細的對需求的分配有提出相對應的方法。
在這篇論文之中，我們詳細定義了各個服務的分配機制，使得每個客戶端的需求都能依照各個連線的狀況而被滿足，此QoS架構包括了最主要的頻寬分配，服務分類及頻寬需求申請的配置。
最後我們以我們所規劃的方法與目前現有機制的比較，結果中可以表現出在頻寬分配的效率方面，此架構不僅可以滿足QoS及公平性，並且有著較有效率的分配。

IEEE 802.16 is considered today as the most promising technology to build a simple, high performance and high bandwidth wireless network into metropolitan areas. For providing a high performance services in complicated environments, QoS (Quality of Service) architecture are designed in IEEE 802.16 for scheduling services for different requests. However, the corresponding mechanisms for scheduling are not described in detail in the standard.
In this paper, we designed an allocation mechanism for different services that could satisfy the requests of SS (Subscriber Station) by the connection conditions. In the allocation mechanism, the bandwidth allocation, services classification and bandwidth request schedule policy are considered.
In the simulation, we have a comparison of the WFQ (Weight Fair Queue) and our algorithm. By the result, it could be observed that our algorithm could not only satisfy the fairness and QoS, but also has better efficiency in scheduling.

目錄

目錄 ………………………………………………………………….………I 
圖目錄 …………………………………………………………………..…..III
表目錄 ………………………………………………………………………V
第一章 導論…………………...……………………………………….....1
1-1 網路發展……………….………………………………………1
1-2 有線網路與無線網路….………………………………………2
1-3 研究主旨………….……………………………………………3
1-4 論文架構………….……………………………………………3
第二章 背景…………………..………………………………………….4
2-1 WiMAX介紹………….…………………………………….....4
2-2 IEEE802.16與WiMAX……….……………………………..10
第三章 QoS架構……………………………………………………….14
3-1 服務類別……………………………………………………...14
3-2 WiMAX中TDD之訊框架構………………………………...19
3-3 服務處理架構………………………………………………...22
第四章 Bandwidth Allocation Mechanism……………………………..26
4-1 系統架構……………………………………………………...26
4-2 設計方法與流程……………………………………………...36
4-2-1 系統初始化……………………………………………38
4-2-2 Pre-Scheduled Time Period Allocation…………………38
4-2-3 Basic CID Allocation…………………………………...40
4-2-4 RST and AST…………………………………………...41
4-2-5 Minimum Bandwidth Allocation of Services…………..44
4-2-6 Polling Request Allocation and rtPS Extra Bandwidth
  Allocation………………………………………………46
4-2-7 Request Schedule Time Allocation of rtPS/nrtPS/BE….48
4-2-8 IE Start Time Assignment…….………………………..53
4-2-9 SS端Scheduler………………………………………..54
4-2-10 SS Service Start Time Assignment………………..56
第五章 模擬環境………………………………….……………………58
5-1 模擬程式……………………………………….…………......58
5-2 WFQ介紹………..…………..……………….……………….61
5-3 模擬結果………………………………………………….…..62
5-3-1 各類型服務之頻寬分配結果……………..………...62
5-3-2 即時性與非即時性服務之頻寬分配結果..………...64
5-3-3 非即時性服務連線數目增加對於即時性服務的影響.
………………………………………………………….65
5-3-4 即時性服務連線數目之增加對於各類型服務之影響.
………………………………………………………….66
5-3-5 與WFQ比較即時性服務之頻寬分配結果……......68
5-3-6 與WFQ比較不同參數時損失率之結果………......69
5-3-7 與WFQ比較系統總損失率之結果…………...…...71
第六章 結論…………………………………………………………….73
參考文獻………………………………………………………………...74







圖目錄

圖2-1-1、全球無線網路的發展規格…………..…………………….….6
圖2-1-2  IEEE 802.16連結IEEE 802.11 WLAN與商業熱點的解決方案..…………………………………………………………………………7
圖2-1-3、IEEE 802.16設計架構………………...……………………..10
圖3-1-1、服務與參數的定義…………………………………………...16
圖3-2-1、IEEE802.16訊框架構………………………………………..19
圖3-2-2、IEEE802.16 下行訊框架構………………………………….20
圖3-2-3、IEEE802.16 上行訊框架構………………………………….20
圖3-2-4、頻寬分配完成之後訊框內容………………………………...21
圖3-3-1、IEEE802.16 Uplink QoS架構………………………………..22
圖3-3-2、Proposed QoS Architecture for SS……………………………24
圖4-1-1、Downlink Subframe Structure with TDD……………………..27
圖4-1-2、Uplink Subframe Structure with TDD…………………………27
圖4-1-3、OFDM Frame Structure with TDD……………………………28
圖4-1-4、Maximum time relevance of DL-MAP and UL-MAP (TDD)…29
圖4-1-5、Minimum time relevance of DL-MAP and UL-MAP(TDD)….29
圖4-1-6、SS與BS間BR產生與傳送過程…………………………….30
圖4-1-7、Time Plan - one TDD Time Frame (with Only Mandatory Zone)……………………………………………………………………...31
圖4-1-8、TDD Scheduling structure with preamble and FCH…………..32
圖4-1-9、SS information table on BS…………………………………….33
圖4-1-10、SS service information table………………………………….34
圖4-1-11、Scheduling process…………………………………………..36
圖4-2-1、Scheduling flowchart of BS……………………………………37
圖4-2-2、DL-MAP structure…………………………………………….39
圖4-2-3、UL-MAP structure…………………………………………….39
圖4-2-4、Uplink pre-scheduled time in subframe……………………….40
圖4-2-5、DL/UL burst structure…………………………………………41
圖4-2-6、Minimum Bandwidth Allocation without Priority……………..45
圖4-2-7、rtPS Extra Bandwidth Allocation………………………………47
圖4-2-8、rtPS, nrtPS, BE Required Scheduled Time period Allocation….49
圖4-2-9、Maximum Bandwidth Allocation without Priority……………51
圖4-2-10、Maximum Bandwidth Allocation with Priority……………….52
圖4-2-11、Arranging Start Time of Each Service…………………...…..53
圖4-2-12、Scheduling flowchart of S…………………………………...54
圖4-2-13、Arranging Start Time of Each Service……………………….57
圖5-1-1、模擬程式中的BS端………………………………………….59
圖5-1-2、模擬程式中的SS端………………………………………….59
圖5-1-3、模擬結果………………………………………………………60
圖5-3-1、在QoS架構下頻寬分配的結果……………………………..63
圖5-3-2、即時性與非即時性服務損失率之比較………………………64
圖5-3-3、非即時性服務的增加對即時性服務的影響…………………65
圖5-3-4、即時性服務數目對損失率的影響……………………………66
圖5-3-5、SS數目對於即時性服務即非即時性服務的影響…………..68
圖5-3-6、服務速率參數對於我們所提出之方法頻寬分配之影響……70
圖5-3-7、服務速率參數對於WFQ頻寬分配之影響………………….70
圖5-3-8、Weight Fait Queue 與 我們所提出的方法之比較………….72





表目錄

表2-1-1、IEEE802.16近期標準………………………………………………8
表3-1-1、各類服務與其相對應的QoS參數…………………….…………18
表4-1-1、系統參數(I)…………………………………………….…………34
表4-2-1、系統參數(II)……………………………………………..………..41
表4-2-2、範例 Bandwidth reallocation table with r=[60%, 30%, 10%]…..50
表5-3-1、SS參數設定(I)……………………….…………………………..62
表5-3-2、模擬結果(I)….……………………………………………………63
表5-3-3、模擬結果(II)..…………………………………………………….64
表5-3-4、SS參數設定(II)………………………………………………….65
表5-3-5、SS參數設定(III)…………………………………………………66
表5-3-6、與WFQ比較之SS參數設定…………………………………..68
表5-3-7、模擬結果(III)…………………………………………………….68
表5-3-8、SS參數設定(IV)…………………………………………………69
表5-3-9、我們所提出方法之模擬結果……………………………………69
表5-3-10、WFQ之模擬結果………………………………………………70
表5-3-11、SS參數設定(V)…………………………………………………71
表5-3-12、我們所提出方法之模擬結果…………………………………..72
表5-3-13、WFQ之模擬結果……………………………………………….72

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