As the popularity of IEEE 802.11 wireless LANs (WLANs) grows rapidly, many new 802.11 wireless standards are emerging. New 802.11 standards are being developed in two major categories: specifications that make use of advanced wireless technologies in Radio Frequency (RF) and Physical layer (PHY), such as 802.11n, and specifications that address the needs in wireless network management, performance measurements, inter-networking, fast roaming, and the needs in other various specific applications and use scenarios. These include 802.11k, 802.11p, 802.11r, 802.11s, 802.11T, 802.11u, 802.11v, 802.11w and 802.11y. In this chapter, we discuss briefly the goals and scopes of these emerging standards. Emphasis will be given on 802.11n standard because of the significance in the technology advances it brings in.

IEEE 802.11n: Enhancements for Higher Throughput

802.11n is a long anticipated upgrade to the IEEE 802.11a/b/g wireless local-area network standards. It is expected to bring significant increase in MAC throughput of over 100 megabits per second (Mbps) and an enhanced communication range in the 2.4 and 5 GHz bands. 802.11n is also required to make efficient use of the unlicensed spectral resources by achieving at least 3 bits per second per Hz at the highest 802.11n rate.

The first draft of 802.11n supports PHY rates as high as 270 Mbps or five times that of a 802.11a/g network, which runs at 54 Mbps. The PHY rates can increase even more, up to 600 Mbps with four spatial streams and 40 MHz bandwidth, in the longer term when more receiver and transmitter antennas are employed.