在無線隨意網路(Wireless Ad Hoc Network)中，用戶間直接通訊可以提高空間重複使用率，但其互相干擾導致封包遺失為重要議題。因此本論文即針對運作於毫米波頻段的隨意網路系統之媒介存取層(MAC)機制並著重於實體層(PHY)中使用指向性或全向性的天線考量及傳送功率控制設計。
在本論文中，我們基於 IEEE 802.11 媒介存取層DCF機制，針對用戶在控制封包 (RTS/CTS)傳送階段，不同傳送/接收天線組合設計對碰撞影響程度及資料吞吐量等系統性能進行理論分析與系統模擬，得證指向性RTS/CTS是較佳設計。由於指向性RTS/CTS只能讓特定方向的用戶偵測以避免並行傳送的干擾，而其他無法接收到RTS/CTS訊號的用戶將視通道為閒置而傳送並造成碰撞問題；因此透過量測通道增益所得資訊來做傳送功率調整將有助於減少用戶間並行通訊造成的干擾，從模擬結果顯示，我們所提的方法可以降低用戶的碰撞機率以及並提高系統的整體能量效益。

The stations that connect directly to each other increases the spatial reuse in wireless ad hoc network. However, the interference s and collision s between stations is an important issue . Hence, this thesis will focus on MAC /PHY layer design and the application of transmit power control.
In this thesis, the MAC layer is based on 802.11 DCF protocol. First, t he several system performance indicators between different kinds RTS/CTS are t heoretically analyzed and simulated . And the simulation results show directional RTS/CTS is much better. However, the directional RTS/CTS only inform the stations in specific direction. Other stations will sense the channel as idle and transmit. It may cause severe collision s . Therefore, this thesis proposes th at adjusting the transmit power through the channel gain information so as to decrease the interference s and collisions .
Simulation results show that our proposed scheme can imp rove the system throughput and enhance the energy efficiency.

[1] IEEE802.11ad-2012, “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 Amendment 3: Enhancements for Very High Throughput in the 60GHz Band,” IEEE Std 802.11ad-2012 (Amendment to IEEE Std 802.11-2012), 2012, pp. 1–628.
[2] Pei Zhou, Kaijun Cheng, Xiao Han, Xuming Fang, Yuguang Fang, Rong He, Yan Long, and Yanping Liu, “IEEE 802.11ay-Based mmWave WLANs: Design Challenges and Solutions,” IEEE Comm. Surveys & Tutorials, vol. 20, no. 3, 2018
[3] Osama Bazan and Muhammad Jaseemuddin, “A Survey On MAC Protocols for Wireless Ad hoc Networks with Beamforming Antennas,” IEEE Communications Surveys & Tutorials, vol. 14, no. 2, Second Quarter 2012, pp. 216-239.
[4] Y. Ko, V. Shankarkumar, and N. Vaidya, “Medium Access Control Protocols Using Directional Antennas in Ad Hoc Networks,” in IEEE International Conference on Computer Communications (INFOCOM), Tel Aviv, Israel, March 2000, pp. 13–21. (DMAC)
[5] R. Choudhury, X. Yang, R. Ramanathan, and N. Vaidya, “Using Directional Antennas for Medium Access Control in Ad Hoc Networks,” in ACM International Conference on Mobile Computing and Networking (Mobicom), Atalanta, Georgia, September 2002, pp. 59–70. (Basic DMAC).
[6] Z. Huang, C. Shen, C. Srisathapornphat, and C. Jaikaeo, “A BusyTone Based Directional MAC Protocol for Ad Hoc Networks,” in IEEE Military Communications Conference (Milcom), vol. 2, Anaheim, California, October 2002, pp. 1233–1238.
[7] R. Choudhury and N. Vaidya, “Deafness: A MAC Problem in Ad HocNetworks when Using Directional Antennas,” in IEEE International Conference on Network Protocols (ICNP), Berlin, Germany, October 2004, pp. 283–292.
[8] Bianchi, Giuseppe. “Performance analysis of the IEEE 802.11 distributed coordination function.” IEEE Journal on selected areas in communications 18.3 (2000): 535-547.
[9] Keysight Technologies Fundamentals of RF and Microwave Noise Figure Measurements, Keysight Technologies
[10] B. Smith and M.H. Carpentier, “The Microwave Engineering Handbook: Microwave systems and applications,” Springer.
[11] IEEE: IEEE 802.11. IEEE Standards for Information Technology.
[12] Hsieh-Cheng Liao, “A Joint Transmit Power Control and Backoff Mechanism to Exploit Capture Effect in IEEE 802.11 WLAN,” National Cheng Kung University Thesis for Master of Science, July, 2014