臺灣博碩士論文加值系統

隨著科技與無線網路技術的快速發展，無論是5G(5th Generation Mobile Networks)、物聯網(Internet of Things，IOT)、LTE(Long Term Evolution)或是Wi-Fi等無線網路技術，都必須要面對在有限的頻寬和大量的無線設備的情況下，提供有效率的資訊傳遞服務，在大量無線設備同時請求連線傳遞資訊時，將會造成封包碰撞而發生網路壅塞(network congestion)阻塞無線通訊網路。為了解決上述之問題，本論文提出一種適應性狀態調整倒退演算法(Adaptive State Backoff Algorithm，ASBA)，結合指數與線性倒退機制的優點，利用在每個階段的碰撞嚴重性設定State值並依照重新傳送次數定義Level值，使碰撞視窗的調節更有效率，改善無線網路在競爭階段效能，並且避免傳輸延遲的發生，以提升整體網路效能。
考量到了相關的倒退演算法研究大部分皆採用NS-2或是數據運算來驗證，為了讓驗證環境更趨近現實狀況，故本論文使用NS-3(network simulator)模擬ASBA與其他倒退演算法在無線網路環境下的效能分析。根據實驗結果表明，ASBA透過網路負載狀態，有效調配碰撞視窗大小，與其他倒退演算法相比較，確實在傳輸吞吐量和碰撞率上表現較為優異。

With the rapid growth of technology and wireless networks, technologies need to provide efficiency information delivery in the case of limited bandwidth and huge wireless devices, no matter 5th Generation Mobile Networks, Internet of Things (IOT), Long Term Evolution (LTE) or Wi-Fi, etc. In the wireless networks, there are numerous requests form different devices at the same time, the network congestion will happen. In this paper, we propose the Adaptive State Backoff Algorithm (ASBA) to solve network congestion. To improve wireless networks performance in contention stage and avoid the delay of delivery,the ASBA adopts effective adjustment of contention widows by using the collision state in every stage. Consider the feasibility of ASBA and the real situation in networks, this paper use NS-3 network simulator to build the wireless environment, and analysis the ASBA performance. The result show that, the throughput and collision rate is better than other backoff algorithm.

摘 要 iv
Abstract v
誌 謝 vi
目 錄 vii
圖 目 錄 ix
表 目 錄 xi
第一章 前言 1
1-1 機器類型通訊的發展簡述 3
1-2 研究動機與目的 4
1-3 論文架構 8
第二章 背景知識與相關研究 9
2-1 背景知識 9
2-1-1 MTC網路架構 9
2-1-2 MTC特徵與應用 12
2-1-3 LTE系統中MTC壅塞現象 14
2-1-4隨機存取程序 16
2-2 相關研究 21
2-2-1 Access Class Barring scheme 21
2-2-2 Separate RACH resources for MTC scheme 22
2-2-3 Dynamic allocation of RACH resources scheme 22
2-2-4 MTC Specific Backoff scheme 22
2-2-5 Slotted Access scheme 22
2-2-6 Pull Based scheme 23
2-2-7 IEEE 802.11 DCF 23
2-2-8 Exponential Increase Exponential Decrease(EIED) 24
2-2-9 Linear Increase Linear Decrease(LILD) 25
第三章 動態退回演算法 27
3-1 DBA演算法設計概念 28
3-2 DBA演算法 31
第四章 模擬實驗與效能分析 33
4-1 模擬環境與參數設定 33
4-2 模擬結果與效能分析 35
4-2-1 Average Access Delay 35
4-2-2 Collision Rate 36
4-2-3 Preamble Collision Counts 37
4-2-4 Preamble Success Counts 38
4-2-5 Average Access Cost 39
第五章 結論與未來工作 40
參考文獻 41

[1]Ericsson Mobility Report 2017, https://www.ericsson.com/mobility-report/
mobile-subscriptions
[2]IEEE 802.11 WG, Reference number ISO/IEC 8802-11: 1999(E) IEEE Std 802.11, 1999 edition. International 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,” 1999.
[3]S. Tozlu, M. Senel, W. Mao, A. Keshavarzian, "Wi-Fi enabled sensors for internet of things: a practical approach," Commun. Mag., vol. 50, no.6, pp. 134–143, 2012
[4]IEEE Std 802.11.Part 11：Wireless LAN Medium Access Con trol（MAC）and Physical Layer（PHY）specifications[S].New York：IEEE Press，2007.
[5]M.A. Visser and M.E. Zarki, “Voice and data transimission over an 802.11 wireless network,” Proc. Personal, Indoor and Mobile Radio Communications Conference, vol. 2, pp. 648-652, Sep. 1995
[6]W.K. Kuo, C.Y. Chan, and K.C. Chen, “Time bounded services and, mobility management in IEEE 802.11 wireless LANs,” Proc. IEEE Personal Wireless Communication Conference, pp. 157-161, 1997.
[7]J. Sanchez, R. Martinez and M. W. Marcellin, “A survey of MAC protocols for wireless ATM," IEEE Network,. 1997. vol. 11, Nov.-Dec
[8]M. Natkanies and A. R. Pach, “An Analysis of the Backoff Mechanism used in IEEE 802.11 Networks,” IEEE Symposium on computer and communication, pp. 444-449, Jul. 2000.
[9]H. Wu, Y. Peng, K. Long, and S. Cheng, ”A simple model of IEEE 802.11 Wireless LAN,” IEEE International Conference on Info-tech and Info-net, vol. 2, pp. 514-519, Nov. 2001.
[10]H. Wu, S. Cheng, Y. Peng, K. Long, and J. Ma, “IEEE 802.11 Distributed Coordination Function (DCF) Analysis and Enhancement,” IEEE International Conference on Communications, vol. 1, No. 28, pp. 605-609, May 2002.
[11]B. J. Kwak, N. O. Song, and L. E. Miller, “Analysis of the Stability and Performance of Exponential Backoff,” IEEE Wireless Communications and Networking Conference, vol. 3, No. 3, pp. 16-20, Mar. 2003.
[12]Y. Xiao, “Backoff-based Priority Schemes for IEEE 802.11,” IEEE International Conference on Communications 2003, vol. 3, pp. 1568-1572, May 2003.
[13]Z. H. Velkov and B. Spasenovski, “Saturation Throughput-Delay Analysis of IEEE
802.11 DCF in Fading Channel,” IEEE International Conference on Communications 2003, vol. 1, pp. 121-126, May 2003.
[14]P. Chatzimisios, A. C. Boucouvalas and V. Vitsas, “IEEE 802.11 Packet Delay – A Finite Retry Limit Analysis,” IEEE Global Telecommunications Conference 2003, vol. 2, pp. 950-954, Dec. 2003.
[15]H. Chen and Y. Li, “Performance Model of IEEE Communication Letters, vol. 8, No. 3, Mar. 2004.
[16]N. O. Song, B. J. Kwak, J. Song, and L. E. Miller. “Enhancement of IEEE 802.11 Distributed Coordination Function with Exponential Increase Exponential Decrease Backoff Algorithm” , in Proc. of VTC 2003 (Spring), New Orleans, 2003
[17]N. Song, B. Kwak, J. Song, and L. E. Miller, “Enhancement of IEEE 802.11 distributed coordination function with exponential increase exponential decrease backoff algorithm, ” The 57th IEEE Semiannual Spring VTC, vol. 4, April 2003.
[18]Bharghavan V., Demers, A., Shenker, S., & Zhang, L. (1994). MACAW: A media access protocol for wireless LAN’s. In Proceeding ACK SIGCOMM’94,
[19]G. Bianchi, L. Fratta, and M. Oliveri, “Performance Evaluation and Enhancement of the CSMA/CA MAC protocol for 802.11Wireless LANs,” in Proc. PIMRC’96, Taipei, Taiwan, pp. 392-396, Oct. 1996.
[20]F. Cali, M.Conti, and E. Gergori, “Dynamic Tuning of the IEEE 802.11 Protocol to Achieve a Theoretical Throughput Limit,” IEEE/ACM Trans. Networking, vol. 8, no. 6, pp. 785-799, Dec. 2000.
[21]D. Qiao and K. G. Shin, “UMAV: A Simple Enhancement to the IEEE 802.11 DCF,” in Proc. The 36th Hawaii International Conference on System Science (HICSS-36), Hawaii, Jan. 2003.
[22]D. J. Deng, C. H. Ke, H. H. Chen, and Y. M. Huang, “Contention Window Optimization for IEEE 802.11 DCF Access Control”, IEEE Transaction on Wireless Communications, vol. 7, No. 12, Dec. 2008.