A MAC proposal to IEEE802.11n high‐throughput WLAN for 20/40 MHz coexistence

IEEE802.11-1999 Standard is widely known as a standard of WLAN and it has a number of amendments and supplements such as 802.11a, 802.11g, and 802.11i and also those under work in the current activities by the task groups (TGs). The one now attracting a great deal of attention is TGn, which is aimed at achieving high throughput. We are involved in this TGn standardization process. To achieve high throughput, MIMO technique is the main discussion point in the PHY layer in TGn. But another important point is the channel bundling method which extends the channel bandwidth from 20 MHz to 40-MHz. By doubling the channel bandwidth, the data rate can be increased. But when this channel bundling method is introduced, the question of how to cope with the legacy 20-MHz stations will arise. For this problem, we are proposing to control the 20-MHz and 40-MHz STAs by setting NAV to them in the MAC layer. This paper explains our coexistence proposal for the system where transmission in both 20-MHz and 40-MHz channel bandwidths is enabled. The performance is also examined to confirm the influence of applying our coexistence proposal. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 90(1): 1–12, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20335