期刊名称：International Journal of Distributed Sensor Networks
印刷版ISSN：1550-1329
电子版ISSN：1550-1477
出版年度：2014
卷号：2014
DOI：10.1155/2014/927192
出版社：Hindawi Publishing Corporation
摘要：Very high throughput (VHT) WLAN, known as IEEE
802.11ac, can provide compelling performance and has attracted
extensive attention for achieving transmission rate over 1 G
bps for 5 GHz band owing to involving the MU-MIMO and maximum
160 MHz bandwidth transmission. Despite extensive studies and
dramatic performance, the conventional carrier sensing mechanism
emerges some drawbacks especially in the overlapping BSS scenario
responsible for employment of MU-MIMO and bandwidth expansion.
In order to address the issue of conventional carrier sensing
mechanism, namely, redundant or useless network allocation vector
(NAV) setting, this paper proposes an enhanced NAV transmission
mechanism, which not only needs little modifications to current
standard draft but also can achieve performance improvement
significantly. On this basis, in order to solve the SINR inaccuracy
calculated based on null data packet (NDP) in the actual MU-MIMO
transmission, the SINR feedback mechanism is proposed
and the frame structure modifications are displayed in detail.
Furthermore, theoretical analysis is also performed on the proposed
mechanism and the formulas of the achieved gains are also derived.
Numerical results confirm the validation of our theoretical analysis
and further substantiate that the proposed scheme obtains obvious
throughput gain over the conventional mechanism.
