802.11n war over, joint standard proposal due
La guerre est finie. The two major coalitions battling each other over the standard for 802.11n have agreed to submit a unified proposal to the IEEE. The two groups, TGn Sync and WWiSE, joined by a small third group, MITMOT, said they would merge their proposals in a draft which will be submitted to the IEEE in September, with a final version due in November.
The compromise was not easy to achieve. Each of the groups enjoyed the backing of big industry names. WWiSE was backed by Texas Instruments, Broadcom, Conexant, STMicro, Airgo, and Bermai. Motorola initially offered its own proposal, but then joined WWiSE, while Nokia initially supported TGn Sync but then switched its support to WWiSE. TGn Sync's roster was not less impressive and included Intel, Atheros, Agere, Infineon, Cisco, Qualcomm, Nortel, Mitsubishi, Sony, Panasonic, Philips, Samsung, Sanyo, and Toshiba.
In March, TGn Sync edged ahead of WWiSE in the Task Group voting but failed to reach the 75 percent necessary to knock the rival group out of the competition. A follow-up vote in May saw TGn Sync's majority shrink, making a continuing deadlock appear all but inevitable. Rather than succumb to UWB's fate, the two groups concluded it made more sense to work together.
Both proposals are based on MIMO technology and OFDM. Both proposals also rely on spatial multiplexing techniques to spread the data over the various antennae, thus turning a serial data steam into multiple parallel streams. The differences between the two have to do with the number of antennas (two or four), and the use of 20MHz or 40MHz channel widths. They also differ in some of the refinements applied to the signals. For example, TGn Sync uses an Extended MCS and Basic Beamforming to bolster the reliability of data links and also claims that its compatibility with 802.11b is less of a question relative to that of WWiSE's scheme.
For more on the joint WWiSE-TGn Sync proposal:
- see Tony Smith's TheRegister report