在水下聲波網路環境中，聲波是作為訊號傳輸的工具。然而聲音的傳播速度(1500 m/s)遠低於光速(3*108 m/s)，因此相較於採用電磁波的資料傳輸，高傳播延遲(High Propagation Delay)將在聲波傳輸環境中造成巨大的影響。尤其以利用四項交握(Four-Way Handshaking)機制來達到避免碰撞的媒介存取協定，不但增加了本身資料傳輸的延遲，還浪費了控制封包與控制封包間未利用的頻寬。為了改善四項交握機制在水下運作的效率，本篇論文提出一個以Handshake-Based的媒介存取控制協定，額外加入一個傳輸機制，有效利用控制封包與控制封包之間的等待時間，增加獲得傳輸資料的機會，提高整體網路效能。
最後根據實驗結果，本論文所提出的一個利用率較高的媒介存取控制協定在效能上有較佳的表現。

Network environment in underwater acoustic networks, acoustic signal transmission as a tool. But the sound propagation speed (1500 m / s) much lower than the speed of light (3 * 108 m / s), so compared to the data transmission using electromagnetic waves, high propagation delay will cause the sonar transmission environment huge impact. Particularly in the use of four-way handshaking mechanism to achieve collision avoidance medium access protocol, not only increases the data transmission delay itself, but also a waste of control packets and control packets between the unused bandwidth. Four handshake mechanism in order to improve the efficiency in the water, this paper presents a handshake-based media access control protocol, a transmission mechanism for adding additional, effective use of control packets and the waiting time between control packets increase get the opportunity to transfer data to improve overall network performance. 
Finally, according to the experimental results, we proposed a high efficiency in the performance of medium access control protocol has better performance.

第1章	緒論	1
1.1	前言	1
1.2	研究動機與目標	1
1.3	研究方法	4
1.4	論文架構	5
第2章	相關文獻	6
2.1	MACA-U(MACA-U: A Media Access Protocol for Underwater Acoustic Networks)	6
2.2	RIPT (RIPT: A Receiver-initiated Reservation-based for Underwater Sensor Networks)	6
2.3	UMACAW (A Delay-tolerant MAC Protocol with Collision Avoidance for Underwater Acoustic Networks)	7
第3章	預備知識	8
3.1	網路架構	8
3.2	相關符號定義	9
3.3	相關假設	10
第4章	Channel Stealing MAC Protocol	11
4.1	隱藏節點問題	11
4.2	基本想法	13
4.3	遭遇問題	14
4.3.1	CTS封包碰撞問題	14
4.3.2	DATA封包碰撞問題	14
4.3.3	干擾問題	15
4.4	Division of Region	16
4.5	Time Slot Segmentation	17
4.6	Channel Stealing MAC Protocol	17
4.6.1	Region I & III	17
4.6.2	Region II	19
第5章	模擬結果	25
第6章	結論	30
參考文獻	31
附錄－英文論文	36

圖目錄
圖1、Four-way handshaking頻寬使用率不佳示意圖	4
圖2、水下場景示意圖	8
圖3、隱藏節點問題造成干擾示意圖	11
圖4、避免節點干擾之示意圖	12
圖5、鄰居傳輸資料的基本概念	13
圖6、鄰居節點的DATA與發送端的CTS碰撞示意圖	14
圖7、鄰居節點的DATA之間碰撞示意圖	15
圖8、干擾問題之示意圖	15
圖9、傳輸對區域之劃分	16
圖10、時槽分割示意圖	17
圖11、在Region I的節點A成功傳輸示意圖	18
圖12、在Region III的節點A成功傳輸示意圖	18
圖13、干擾問題示意圖	19
圖14、干擾最少之最佳情形示意圖	20
圖15、時槽與橢圓選擇轉換示意圖	21
圖16、合適橢圓之選擇示意圖	22
圖17、相對座標計算示意圖	23
圖18、Throughput 與 Offered load 之關係	26
圖19、Channel utilization 與 Number of nodes 之關係	27
圖20、Average delay 與 Offered traffic load 之關係  	28

表目錄
表1、模擬參數	25

[1]N. Chirdchoo, W. S. Soh, and K. C. Chua, “Aloha-based MAC Protocols with Collision Avoidance for Underwater Acoustic Networks,” in Proceeding of IEEE International Conference on Computer Communications (INFOCOM), May 2007.

[2]N. Chirdchoo, W. S. Soh, and K. C. Chua, “MACA-MN: A MACA-based MAC Protocol for Underwater Acoustic Networks with packet Train for Multiple Neighbors,” in Proceeding of IEEE Vehicular Technology Conference (VTC), 2008.

[3]N. Chirdchoo, W. S. Soh, and K. C. Chua, “RIPT : A Receiver-initiated Reservation-based Protocol for Underwater Acoustic Networks,” in Proceeding of IEEE Journal on Selected Areas in Communications (JSAC), Dec. 2008.

[4]P. Guo, T. Jiang, G. Zhu and H.-H. Chen, “Utilizing acoustic propagation delay to design MAC protocols for underwater wireless sensor networks,” in Proceeding of Wireless Communications and Mobile Computing (WCMC), 2008.

[5]X. Guo, M. Frater, and M. Ryan, “A Propagation-delay-tolerant Collision Avoidance Protocol for Underwater Acoustic Sensor Networks,” in Proceeding of OCEANS Asia Pacific, pp.1–6, 2006.

[6]J. Heidemann, W. Ye, J. Wills, A. Syed, and Y. Li, “Research challenges and applications for underwater sensor networking,” in Proceeding of IEEE Wireless Communications and Networking Conference (WCNC), 2006.

[7]M. Molins and M. Stojanovic, “Slotted FAMA: A MAC protocol for underwater acoustic networks,” in Proceeding of OCEANS Asia Pacific, May 16–19, 2006.

[8]H. H. Ng, W. S. Soh, and M. Motani, “MACA-U: A Media Access Protocol for Underwater Acoustic Networks,” in Proceeding of the IEEE Global Telecommunications Conference (GLOBECOM), Dec. 2008.

[9]Y.X Zhong, J.G Huang and J. Han, “A Delay-tolerant MAC Protocol with Collision Avoidance for Underwater Acoustic Networks,” in Proceeding of Wireless Communications, Networking and Mobile Computing(WiCOM), Oct. 2009.

[10]A. Syed, W. Ye, and J. Heidemann, “T-Lohi: A new class of MAC protocols for underwater acoustic sensor networks,” in Proceedings of the IEEE INFOCOM, the Annual Joint Conference of the IEEE Computer and Communications Societies, 
Apr. 2008, pp. 231–235.

[11]H. Ng, W.S. Soh and M. Motani, "ROPA：A MAC Protocol for Underwater Acoustic Networks with Reverse Opportunistic Packet Appending" in Proceeding of the IEEE Wireless Communications and Networking Conference (WCNC), April 2010, pp. 18-21.

[12]D. Shin and D. Kim, “Ordered CSMA: a collision-free MAC protocol for underwater acoustic networks,” in Proceedings of the OCEANS, Oct. 2007, pp. 1–6.

[13]K. B. K. II and P. Mohapatra, “A hybrid medium access control protocol for underwater wireless networks,” in Proceedings of the ACM International Conference on Mobile Computing and Networking (MOBICOM), 2007, pp. 33–40.

[14]K. Kredo, P. Djukic, and P. Mohapatra, “STUMP: Exploiting position diversity in the staggered TDMA underwater MAC protocol,” in Proceedings of the IEEE INFOCOM, the Annual Joint Conference of the IEEE Computer and Communications Societies, Apr. 2009, pp. 2961– 2965.

[15]C.-C. Hsu, K.-F. Lai, C.-F. Chou, and K.-J. Lin, “ST-MAC spatial-temporal MAC scheduling for underwater sensor networks,” in Proceedings of the IEEE INFOCOM, the Annual Joint Conference of the IEEE Computer and Communications Societies, 2009, pp. 1827–1835.

[16]T. N. Nguyen, S.-Y. Shin, and S.-H. Park, “Efficiency reservation MAC protocol for underwater acoustic sensor networks,” in Proceedings of the International Conference on Networked Computing and Advanced Information Management (NCM), vol. 1, 2008, pp. 365–370.

[17]L. Hong, F. Hong, Z. Guo, and X. Yang, “A TDMA-based MAC protocol in underwater sensor networks,” in Proceedings of the International Conference on Wireless Communications, Networking and Mobile Computing (WiCOM), Oct. 2008, pp. 1–4.

[18]X. Guo, F. M.R., and R. M.J., “An adaptive propagation-delay-tolerant MAC protocol for underwater acoustic sensor networks,” in OCEANS Europe, 2007, pp. 1–5.

[19]P. Guo, T. Jiang, G. Zhu, and H.-H. Chen, “Utilizing acoustic propagation delay to design MAC protocols for underwater wireless sensor networks,” IEEE Communications Letters, vol. 9, pp. 1035–1044, Oct. 2008.

[20]Z. Guo, Z. Li, and F. Hong, “USS-TDMA: Self-stabilizing TDMA algorithm for underwater wireless sensor network,” in Proceedings of the International Conference on Computer Engineering and Technology (ICCET), vol. 1, Jan. 2009, pp. 578 – 582.

[21]LinkQuest, “http://www.link-quest.com/”.