总览 评价 赵力强 * （ 西安电子科技大学综合业务网国家重点实验室
） 摘要： Directional distributed coordination function (D-DCF), a modified medium access control protocol of IEEE 802
11, is proposed in this paper to support smart adaptive array antennas over WLAN
D-DCF based on hybrid virtual carrier sense (HVCS) mechanism can coexist with DCF
A smart antenna has omni-directional and directional mode in operation
In D-DCF, before sending any data-frames, the sender and receiver node transmit a pilot sequence by means of omni-directional request-to-send/clear-to-send (ORTS/OCTS) 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 directional mode
The other nodes save the transmission time between the sender and receiver in omni-directional mode in their network allocation vectors
When the sender and receiver communicate in directional mode, the other nodes can contend channel to send their data-frames
Hence, D-DCF supports space division multiple access (SDMA)
关键词： WLAN, Smart Adaptive Array Antennas, MAC, SDMA, TDD Liqiang Zhao * （ State Key Laboratory of Integrated Services Networks, Xidian University
） Abstract： Directional distributed coordination function (D-DCF), a modified medium access control protocol of IEEE 802
11, is proposed in this paper to support smart adaptive array antennas over WLAN
D-DCF based on hybrid virtual carrier sense (HVCS) mechanism can coexist with DCF
A smart antenna has omni-directional and directional mode in operation
In D-DCF, before sending any data-frames, the sender and receiver node transmit a pilot sequence by means of omni-directional request-to-send/clear-to-send (ORTS/OCTS) 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 directional mode
The other nodes save the transmission time between the sender and receiver in omni-directional mode in their network allocation vectors
When the sender and receiver communicate in directional mode, the other nodes can contend channel to send their data-frames
Hence, D-DCF supports space division multiple access (SDMA)
Moreover, D-DCF supports both forward and backward transmission in one access period
Simulation results show that D-DCF can support smart antennas effectively and provide much higher network throughput, lower delay, jitter and packet-loss-rate than DCF does
Keywords： WLAN, Smart Adaptive Array Antennas, MAC, SDMA, TDD 下载PDF阅读器 PDF全文下载： 初稿 （ 360 ） 作者简介： 通信联系人： 【收录情况】 中国科技论文在线： 赵力强
Adaptive Antenna System in IEEE 802
11 WLAN[EB/OL]
北京：中国科技论文在线
[2006-09-04]
http://www
paper
edu
cn/releasepaper/content/200609-41
