The new generation of IEEE 802.11n-based Wi-Fi standards is expected to pick up significant market momentum in 2008. Draft 2.0 of the 802.11n amendment to the standard is now widely considered stable, with only minor changes from draft 1.0.Tests conducted by vendors and independent test labs show that draft 802.11n products reach up to twice as far and are as much as five times as fast as legacy 802.11a/b/g technology. The currently available draft 802.11n technology can comfortably cover a typical house with sufficient bandwidth to support video, gaming, data and voice applications.
The developing IEEE 802.11n standard is based on MIMO (multiple-input multiple-output) air interface technology. MIMO is a significant innovation and a technology that is being adapted for use by several non-802.11 wireless data communications standards, including 4G cellular. MIMO employs a technique called spatial multiplexing to transport two or more data streams simultaneously in the same frequency channel. Spatial multiplexing is central to 802.11n and has the potential of doubling the throughput of a wireless channel when two spatial streams are transmitted. Generating multiple spatial streams requires multiple transmitters, multiple receivers and distinct, uncorrelated paths for each stream through the medium. Multiple paths can be achieved using antenna polarization or multipath in the channel.