跳到主要內容

臺灣博碩士論文加值系統

(44.192.20.240) 您好!臺灣時間:2024/02/24 01:03
字體大小: 字級放大   字級縮小   預設字形  
回查詢結果 :::

詳目顯示

我願授權國圖
: 
twitterline
研究生:賴彥文
研究生(外文):Yan-Wun Lai
論文名稱:IEEE802.11無線區域網路的效能評估
論文名稱(外文):Performance Analysis of IEEE 802.11-based Networks
指導教授:紀光輝
指導教授(外文):Kuang-Hui Chi
學位類別:碩士
校院名稱:國立雲林科技大學
系所名稱:電機工程系碩士班
學門:工程學門
學類:電資工程學類
論文種類:學術論文
論文出版年:2006
畢業學年度:94
語文別:中文
論文頁數:89
中文關鍵詞:無線區域網路
外文關鍵詞:IEEE 802.11throughput
相關次數:
  • 被引用被引用:0
  • 點閱點閱:251
  • 評分評分:
  • 下載下載:0
  • 收藏至我的研究室書目清單書目收藏:0
分散式協調功能(Distributed Coordination Function,DCF)是IEEE 802.11媒體存取控制(Medium Access Control)層的基本存取方法,它利用載波偵測多重存取碰撞避免(Carrier Sense Multiple Access With Collision Avoidance)的技術來控制傳輸媒介的存取,DCF有兩種用來傳輸資料訊框的機制,一種為Basic存取機制,另一種為RTS/CTS存取機制。
我們採用一個基於馬可夫鏈(Markov chain)的分析模型來研究IEEE 802.11b高速直接序列展頻實體層之無線區域網路效能,考慮封包重傳限制及工作站避免封包碰撞,所產生的後退時間(backoff time)。而IEEE 802.11 b支援兩種Preamble的長度:Long Preamble與 Short Preamble,Long Preamble支援的四種資料傳輸速率分別是1、2、5.5及11 Mbps,選項規格的Short Preamble所支援的三種資料傳輸速率分別是2、5.5及11 Mbps。所以我們分別使用Basic存取機制與RTS/CTS存取機制來進行Long Preamble與Short Preamble的訊框傳送,並進行網路流量分析。
在本論文中,我們分析無線區域網路之分散式協調功能在多重傳輸速率下的網路流量效能、封包傳送機率、封包碰撞機率。分析結果顯示當工作站傳送的訊框發生碰撞而必須進行重送的程序,此時後退階段(backoff stage)增加,傳送機率將隨著後退階段增加而減少,並隨工作站數目增加而減少。而碰撞機率將隨著後退階段增加而減少,並隨工作站數目的增加而增加。此時,無線區域網路流量將隨著退階段增加而增加,並隨工作站數目的增加而減少。而當工作站以Short Preamble來進行訊框傳送,確實可增加網路流量效能。此外本論文的分析模型亦可適用於IEEE 802.11g環境中。
本論文將使用IEEE 802.11 MAC的分散式協調功能之Basic存取機制與RTS/CTS存取機制,針對IEEE 802.11b高速直接序列展頻實體層,使用Mathcad軟體來進行無線區域網路的效能評估,並由分析數據歸納出結論與建議。
The distributed coordination function (DCF) is essential for IEEE 802.11 medium access control (MAC) services. DCF employs a carrier sense multiple access with collision avoidance technique, defining two mechanisms for data frame transmissions with or without using RTS (Request to Send) and CTS (Clear to Send) frame exchanges beforehand. The former is referred to as the RTS/CTS access mechanism, while the latter is the basic access mechanism.
In this thesis we use a Markov chain to model IEEE 802.11 networking behavior under the DCF. Under consideration is the IEEE 802.11b High Rate direct sequence spread spectrum physical layer. We take into account the retry limit and backoff time whereby wireless stations avoid collisions of transmitted packets. Additionally we consider two types of preambles (long and short) as per IEEE 802.11b. The long preamble mode supports transmission rates of 1, 2, 5.5, and 11 Mbps, whereas the short preamble supports transmission rates of 2, 5.5, and 11 Mbps. We study the throughput of IEEE 802.11 networks in terms of the probabilities of packet transmissions and collisions in multiple transmission rates. Our performance analysis is carried out quantitatively using the RTS/CTS and basic access mechanisms, meanwhile in the context of long and short preambles, respectively.
Analytical results explicitly show the relationship between packet collisions and retransmissions by a varying number of stations following the exponential backoff procedure. It can be seen that the probability of successful transmissions decreases when the backoff stage increases and when the number of stations contending for channel access increases. In addition, the probability of colliding packets is reduced along with the increasing backoff stage but increases as the number of stations increases. Further, the network throughput increases along with the increasing backoff stage but decreases when the number of contending stations grows larger. Moreover, performance results indicate that transmissions in short preamble mode can generally achieve a higher throughput as opposed to transmissions in long preamble mode. Our analytical model applies to IEEE 802.11g settings as well.
中文摘要 ------------------------------------------------------ i
英文摘要 ------------------------------------------------------ ii
誌謝 ------------------------------------------------------ iv
目錄 ------------------------------------------------------ v
表目錄 ------------------------------------------------------ vii
圖目錄 ------------------------------------------------------viii
第一章 緒論-------------------------------------------------- 1
1.1 研究動機與目的---------------------------------------- 2
1.2 研究方法與內容---------------------------------------- 2
1.3 論文架構---------------------------------------------- 2
第二章 IEEE 802.11 MAC簡介----------------------------------- 3
2.1 分散式協調功能---------------------------------------- 3
2.1.1 載波偵測功能與網路配置向量---------------------------- 3
2.1.2 訊框間隔---------------------------------------------- 4
2.2 DCF模式的競爭存取------------------------------------- 6
2.3 後退機制---------------------------------------------- 6
2.3.1 後退程序---------------------------------------------- 9
2.4 IEEE 802.11 MAC訊框格式------------------------------- 9
2.4.1 Frame Control欄位------------------------------------- 10
2.4.2 Duration/ID欄位--------------------------------------- 13
2.4.3 Address欄位------------------------------------------- 14
2.4.4 Sequence Control欄位---------------------------------- 14
2.4.5 Frame Body-------------------------------------------- 15
2.4.6 訊框檢查序列------------------------------------------ 15
2.5 ACK--------------------------------------------------- 15
2.6 RTS/CTS機制------------------------------------------- 16
2.6.1 RTS Threshold----------------------------------------- 16
2.7 IEEE 802.11實體層架構--------------------------------- 17
第三章IEEE 802.11b與IEEE 802.11g實體層--------------------------- 19
3.1 IEEE 802.11b Long PLCP PPDU格式----------------------- 19
3.2 IEEE 802.11b Short PLCP PPDU格式---------------------- 21
3.3 IEEE 802.11g操作模式---------------------------------- 23
第四章關於無線區域網路效能評估的相關研究------------------------- 27
4.1 Tay-Chua分析模型-------------------------------------- 27
4.2 Yeo-Agrawala分析模型---------------------------------- 28
4.3 Bianchi分析模型--------------------------------------- 30
4.4 Throughput Analysis of IEEE 802.11 MAC----------------- 32
4.5 Dong-Varaiya分析模型---------------------------------- 34
第五章 分析模型---------------------------------------------- 38
5.1 封包傳送機率------------------------------------------ 38
5.2 流量分析---------------------------------------------- 44
第六章 效能評估結果------------------------------------------ 48
6.1 參數設定---------------------------------------------- 48
6.2 分析結果---------------------------------------------- 49
6.2.1 傳送機率之分析與研究---------------------------------- 49
6.2.2 碰撞機率之分析與研究---------------------------------- 50
6.2.3 Long preamble下使用Basic與RTS/CTS存取機制之流量分析--- 50
6.2.4 Short preamble下使用Basic與RTS/CTS存取機制之流量分析-- 59
6.2.5 不同存取機制下的封包長度與網路流量之分析與研究-------- 66
6.3 本章結論---------------------------------------------- 68
第七章 結論與未來研究方向------------------------------------ 69
參考文獻 ------------------------------------------------------ 71
附錄 ------------------------------------------------------ 73
A.中樞協調功能----------------------------------------- 73
B.免競爭週期的結構與時序------------------------------- 73
C. PCF存取程序----------------------------------------- 75
D. PCF傳輸程序----------------------------------------- 76
E.輪詢名單的建立與維護--------------------------------- 77
作者簡歷 ------------------------------------------------------ 78
[1] IEEE Std 802.11-1997 Information Technology- telecommunications And
Information exchange Between Systems-Local And Metropolitan Area Networks-
specific Requirements-part 11: Wireless Lan Medium Access Control (MAC)
And Physical Layer (PHY) Specifications,1997.
[2] ANSI/IEEE Std 802.11-1999 Information technology- Telecommunications and
information exchange between systems- Local and metropolitan area networks- Specific requirements- Part 11: Wireless LAN Medium Access Control (MAC)
and Physical Layer (PHY) Specifications,1999.
[3] IEEE Std 802.11b-1999 Supplement To IEEE Standard For Information
Technology- Telecommunications And Information Exchange Between Systems-
Local And Metropolitan Area Networks- Specific Requirements- Part 11:
Wireless LAN Medium Access Control (MAC) And Physical Layer (PHY)
Specifications: Higher-speed Physical Layer Extension In The 2.4 GHz
Band,1999.
[4] IEEE Std 802.11a-1999 Supplement to IEEE standard for information
technology telecommunications and information exchange between systems-
local and metropolitan area networks - specific requirements. Part 11:
wireless LAN Medium Access Control (MAC) and Physical Layer (PHY)
specifications: high-speed physical layer in the 5 GHz band,1999.
[5] IEEE Std 802.11g-2003 IEEE standard for information technology-
telecommunications and information exchange between systems- local and
metropolitan area networks- specific requirements Part II: wireless LAN
medium access control (MAC) and physical layer (PHY) specifications,2003.
[6] J. Yeo and A. Agrawala, “Packet error model for the IEEE 802.11 MAC
protocol”,in Proc. PIMRC,Vol.2,pp. 1722–1726,Sept. 2003.
[7] G. Bianchi, “IEEE 802.11—Saturation Throughput Analysis”,IEEE
Communications Letters, Vol. 2,Issue 2, pp.318–320, Dec. 1998.
[8] G. Bianchi. “Performance Analysis of the IEEE 802.11 Distributed
Coordination Function”, IEEE Journal on Selected Area in Comm. Vol.18,
No.3, pp. 535–547, March. 2000.
[9] P. Chatzimisios, V. Vitsas and A.C. Boucouvalas,“Throughput and Delay
analysis of IEEE 802.11 protocol”,in Proc.of IEEE International Workshop
on Networked Appliances(IWNA),pp. 168–174, Oct. 2002.
[10] P. Ferre,A. Doufexi,A. Nix,D. Bull,“Throughput analysis of IEEE 802.11
and IEEE 802.11e MAC”,IEEE Wireless Communications and Networking
Conference, Vol.2, pp.783 – 788, March. 2004.
[11] Y. C. Tay , K. C. Chua, “A capacity analysis for the IEEE 802.11 MAC
protocol”, Wireless Networks, Vol.7, Issue 2 , pp.159–171, March. 2001.
[12] Matthew S.,Gast., 802.11 wireless networks :the definitive guide,
O''Reilly,Sebastopol,2003.
[13] G. Bianchi,L. Fratta and M. Oliveri, “Performance evaluation and
enhancement of the CSMA/CA MAC protocol for 802.11 wireless LANs, in
Proc. PIMRC, pp. 392–396,Oct. 1996.
[14] I.-H.Lin, J.-Y. Pan, “Throughput analysis of a novel backoff algorithm
for IEEE 802.11 WLANs”, Wireless Telecommunications Symposium,pp. 85–
90, April. 2005.
[15] T.S. Rappaport, Wireless Communications: Principles and Practice.
Prentice Hall,2002.
[16] O. Tickoo,B. Sikdar,“On the impact of IEEE 802.11 MAC on traffic
characteristics”,IEEE Journal on Selected Areas in Communications,
Vol.21, No.2,pp.189–203, Feb. 2003.
[17] K.Takahashi, “Performance Analysis of a Backoff Algorithm using Finish
Tags in IEEE 802.11 Networks”,Asia-Pacific Conference on Communications,
pp. 600–604,Oct. 2005.
[18] Q. Ni,I. Aad,C. Barakat and T. Turletti, “Modeling and analysis of slow
CW decrease for IEEE 802.11 WLAN”, in Proc. PIMRC, Vol.2, pp.1717-1721,
sep. 2003.
[19] X. J. Dong,P. Varaiya, “Saturation throughput analysis of IEEE 802.11
wireless LANs for a lossy channel”,IEEE Communications Letters, Vol.9,
Issue 2, pp.100–102, Feb. 2005.
[20] P. Chatzimisios, A. C. Boucouvalas and V. Vitsas, “IEEE 802.11 Packet
Delay – A Finite Retry Limit Analysis”,in Proc. of IEEE Globecom,
Vol.2,pp. 950–954,Dec. 2003.
[21] P. Chatzimisios, A.C. Boucouvalas and V. Vitsas, “Packet delay analysis
of the IEEE 802.11 MAC protocol”,IEE Electronic Letters,Vol.39,No.18,
pp.1358–1359,Sep. 2003.
[22] P. Chatzimisios, A.C. Boucouvalas and V. Vitsas, “Optimisation of
RTS/CTS handshake in IEEE 802.11 wireless LANs for maximum
performance”,IEEE Global Telecommunications Conference Workshops,pp.
270 – 275, Nov. 2004.
QRCODE
 
 
 
 
 
                                                                                                                                                                                                                                                                                                                                                                                                               
第一頁 上一頁 下一頁 最後一頁 top