在無線隨意網路中，IEEE 802.11 DCF是最重要的MAC協定。DCF利用CSMA/CA及交換RTS、CTS封包的機制降低碰撞發生的機率。收到RTS、CTS封包的節點必須延後傳送封包的時間點，避免和正在傳送封包的節點發生碰撞，造成無法有多個傳送活動能同時發生，抑制了通道使用率。在本論文中我們提出將限制傳送功率的訊息加在控制訊框中，限制鄰近節點封包的發射功率，對接收端造成的干擾在容許範圍內，允許同時發生二個傳送活動。因此，增加了傳送的效率，資料封包的延遲也隨之減少。

The Distributed Control Function (DCF) of the IEEE 802.11standard is dominant MAC protocol for ad hoc networks. This protocol generally follows the CSMA/CA paradigm and uses four-way handshake to resolve channel contention. Any node that receives the RTS or the CTS packets defers its transmission until the ongoing transmission is over. It negatively impacts the channel utilization by not allowing concurrent transmissions to take place. We insert power control information into the control packet and use it to bound the transmission power of potential interfering terminals in the vicinity of the receiver to achieve two concurrent transmissions. Therefore, we not only improve the network throughput, but also reduce the delay of packet.

[1].IEEE, ”Wireless LAN Medium Access Medium Access Control(MAC) and Physical Layer (PHY) specifications.” IEEE Standard 802.11, June, 1999.
[2].O’REILLY, ‘802.11 Wireless Networks: The Definitive Guide, Second Edition’, April 2005.
[3].IEEE Standard for Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications Amendment 4: Further Higher Data Rate Extension in the 2.4 GHz Band, (802.11g), June. 2003
[4].The CMU Monarch Projects Wireless and Mobility Extensions to ns. URL: http://www.monarch.cs.cmu.edu/, 2000-04-25, work in progress.
[5].Network Simulator—NS2, Univ. California, Berkeley, CA, 2004.
[6].A. Muqattash and M. Krunz, “Power controlled dual channel (PCDC) medium access protocol for wireless ad hoc networks.” in Proc. IEEE INFOCOM Conf., 2003
[7].A. Muqattash and M. Krunz, “POWMAC: A single-channel power-control protocol for throughput enhancement in wireless ad hoc networks.” in IEEE Journal on Selected Area on Communication, VOL. 23, NO. 5, May 2005.
[8].F. Cuomo, C. Martello, A. Baiocchi and F. Capriotti, “Radio Resource Sharing for Ad Hoc Networking With UWB.” in IEEE Journal on Selected Area on Communication, VOL. 20, NO. 9, December 2002.
[9].A. Muqattash and M. Krunz, “A distributed transmission power control protocol for mobile ad hoc networks.” in IEEE Transactions on Mobile Computing, Volume 3, Issue 2, April-June 2004.
[10].Kuei-Ping Shih and Yen-Da Chen, “CAPC: a collision avoidance power control MAC protocol for wireless ad hoc networks.” in IEEE Communications Letters Volume 9, Issue 9, Sep 2005.
[11].J. Yee and H. Pezeshki-Esfahani, “Understanding wireless lan performance trade-offs.” in CommsDesign.com, Nov. 2002.
[12].E. Lopez-Aguilera, J. Casademont and J. Cotrina, “Outdoor IEEE 802.11g cellular network performance.” in IEEE GLOBECOM Conf., Dec. 2004.
[13].K. Xu, M. Gerla, and S. Bae, “How effective is the IEEE 802.11 RTS/CTS handshake in ad hoc network?” in Proceedings of the IEEE GLOBECOM Conference, volume 1, page 72-76, Nov. 2002.
[14].S.-C. Wang, Y.-M. Chen, Tsern-Huei Lee ,and A. Helmy, “Performance evaluations for hybrid IEEE 802.11b and 802.11g wireless networks.” in IPCCC, April 2005.
[15].T. Rapppaport, Wireless Communication: Principles and Practice. Prentice-Hall, 2002.