Agere Systems announced a 802.11n proposal that would push raw Wi-Fi link rates to 500 Mbps while retaining backwards compatibility with existing Wi-Fi specifications. Agere said its proposal, to be submitted to the IEEE this summer, incorporates continued innovations in multiple-input multiple-output (MIMO) techniques, as well as wide bandwidth channels, 5 GHz transmissions and numerous operating modes to ensure robust data throughput, increased network capacity and legacy protocol compatibility. MIMO increases data throughput on a single channel by creating more “air paths” for the data to be transmitted. Using multiple transmit and receive antennas, each path can carry a different set of data at the same frequency.
Higher data rates are also achieved using 40/20 megahertz (MHz) channel widths. Agere’s proposal supports both 20 and 40 MHz channel widths, allowing for worldwide operation and increased data capacity. The 40 MHz channels, consisting of two adjacent 20 MHz channels, will more than double the current 54 Mbps data rates to approximately 125 Mbps per transmission. In 2002, Agere demonstrated a 3×3 (three transmitter/three receiver) MIMO system supporting 162 Mbps wireless networking speeds.
Finalization of the 802.11n specification is expected to be completed by the IEEE in 2006.
Agere predicts that target applications for the proposed 802.11n standard would fall into two basic groups — those requiring high-speed data transmissions plus strong QoS, and those that need the equivalent of wired network performance for such high-density environments as a large enterprise or apartment complex. http://www.agere.com
