Research On SDMA Algorithm Based On Adaptive Array Antennas Beamforming Within IEEE 802.11n

The existing wireless local area network (WLAN) system is point to point communication mode, the system throughput is relatively low, however by using spatial division multiple accesses (SDMA), Access Point equipped with Adaptive Antenna Array uses beamforming(BF) technique, shapes beams pointed to the particular STAs, and transmits different datas to different stations,which enhance the system downlink throughtput greatly.This paper mainly studies how the SDMA can be used in the WLAN and has a good compatibility with it.This paper first describes the structure of the WLAN and the MAC protocol, and then a brief introduction of smart antenna and beamforming algorithm, and in finally, proposes two SDMA algorithms, the blind SDMA access and visual SDMA access, based on the existing beamforming algorithms and MAC protocols.The proposed algorithm not only has a good compatibility with the WLAN, but also supports the IEEE 802.11n. Meanwhile, the simulation shows that the two schemes enhance the WLAN's downlink throughtput greatly, and the later scheme has a better performance.