The battle for 11n

When we talk of the IEEE's forthcoming 802.11n standard for high-speed (200Mbit/sec. and up) wireless networks, it's important to note that we're not yet sure what technology it will encompass. Currently, two groups are pushing different approaches. One consortium is the World Wide Spectrum Efficiency (WWiSE), and the other has the rather odd name of TGn Sync (short for Task Group N of the IEEE 802.11 Working Group). First proposals were made in 2004, and there is little hope for agreement before this summer.

TGn Sync is a group of more than 25 companies across cellular, computing, consumer electronics, enterprise networking, mobile radio, public access and semiconductor markets. It is spearheaded by Agere Systems Inc., Atheros Communications Inc., Intel Corp., Nokia Corp, Philips Electronics NV and Sony Corp. The TGn Sync proposal expects to deliver speeds of around 313Mbit/sec. using two antennas and 40-MHz channels.

WWiSE is led by MIMO pioneer Airgo Networks Inc., with other wireless chip-set manufacturers, including Broadcom Corp., Conexant Systems Inc., STMicroelectronics NV and Texas Instruments Inc. The WWiSE proposal requires only a 20-MHz channel (which the group believes is friendlier to all countries) and provides better efficiency. Speeds would start at 135Mbit/sec., with two transmitting antennas mandatory. More antennas would be optional, as would a 40-MHz mode, and these could drive data rates up to 540Mbit/sec.

Currently, TGn Sync's proposal has more proponents but still not enough support for a final decision. In the end, whichever proposal can win 75 percent of the vote will determine the standard. Best guess is that an 802.11n specification will be published in 2007.