Directional distributed co-ordination function - a medium access control protocol to simultaneously support both omni-directional and smart antennas in a same WLAN cell

Directional distributed co-ordination function (D-DCF), a modified medium access control protocol of IEEE 802.11, is proposed to support hybrid antennas such as smart adaptive array antennas and normal omni-directional antennas, in one wireless local area network cell. Nodes equipped with smart antennas follow D-DCF and nodes equipped with normal antennas follow DCF. D-DCF based on a hybrid virtual carrier sense mechanism maintains compatibility with DCF. In D-DCF, before sending any data-frames, the sender and receiver node transmit a pilot sequence by means of an omni-directional request-to-send/clear-to-send handshake mechanism. Based on the pilot, the directional beam can be formed by the smart antenna. Then the node can transmit its data-frame in the directional mode. The other nodes save the transmission time between the sender and receiver in the omni-directional mode in their network allocation vectors. When the sender and receiver communicate in the directional mode, the other nodes can access the channel to send their data-frames. Hence, D-DCF supports space division multiplexing. Moreover, D-DCF fully supports time division duplex, namely both the forward and backward transmission in one access period. Simulation results show that D-DCF can support the hybrid antenna system effectively and provide much higher network throughput, lower delay, jitter and packet-loss-rate than DCF does.

[1]  A. Girotra,et al.  Performance Analysis of the IEEE 802 . 11 Distributed Coordination Function , 2005 .

[2]  Robert E. Hiromoto,et al.  A MAC protocol for mobile ad hoc networks using directional antennas , 2000, 2000 IEEE Wireless Communications and Networking Conference. Conference Record (Cat. No.00TH8540).

[3]  Srikanth V. Krishnamurthy,et al.  Polling-based media access protocols for use with smart adaptive array antennas , 2001, TNET.

[4]  Yang Xiao A simple and effective priority scheme for IEEE 802.11 , 2003, IEEE Commun. Lett..

[5]  Jun Yang,et al.  MAC protocol for mobile ad hoc network with smart antennas , 2003 .

[6]  Fan Chang-xin MAC protocol of WLAN using smart adaptive array antennas , 2004 .

[7]  Liqiang Zhao,et al.  Enhancement of QoS differentiation over IEEE 802.11 WLAN , 2004, IEEE Communications Letters.

[8]  Nitin H. Vaidya,et al.  Medium access control protocols using directional antennas in ad hoc networks , 2000, Proceedings IEEE INFOCOM 2000. Conference on Computer Communications. Nineteenth Annual Joint Conference of the IEEE Computer and Communications Societies (Cat. No.00CH37064).

[9]  Theodore Antonakopoulos,et al.  CSMA/CA performance under high traffic conditions: throughput and delay analysis , 2002, Comput. Commun..

[10]  Haitao Wu,et al.  Performance of reliable transport protocol over IEEE 802.11 wireless LAN: analysis and enhancement , 2002, Proceedings.Twenty-First Annual Joint Conference of the IEEE Computer and Communications Societies.

[11]  Zhao Li TCP Performance Analysis and Enhancement of IEEE 802.11 WLAN , 2005 .

[12]  Robert E. Hiromoto,et al.  On-demand routing using directional antennas in mobile ad hoc networks , 2000, Proceedings Ninth International Conference on Computer Communications and Networks (Cat.No.00EX440).

[13]  Periklis Chatzimisios,et al.  IEEE 802.11 packet delay-a finite retry limit analysis , 2003, GLOBECOM '03. IEEE Global Telecommunications Conference (IEEE Cat. No.03CH37489).