dcsimg
RealTime IT News

TI's 802.11g Specifications Taken Out of Running

The Institute of Electrical and Electronics Engineers (IEEE) on Wednesday voted for a specification proposed by Intersil to transmit data at twice the current rate over wireless local area networks (WLANs), eliminating a competing specification proposed by Texas Instruments.

Of the total, 58 percent voted in favor of Intersil's Orthogonal Frequency Division Multiplexing (OFDM) modulation for so-called "turbo" operation in the unlicensed 2.4GHz spectrum while 42 percent voted for TI's Packet Binary Convolution Coding (PBCC) technology. Both companies were hoping to gain acceptance as the industry standard to be used on chipsets for all next-generation 802.11g products -- which will transmit data at rates at 20+ megabits per second (Mbps).

The vote was a huge blow for Texas Instruments (TI). The Dallas-based company had been working on its PBCC specification for over two years and invested at least $300 million of its own stock in an acquisition to help with those development efforts.

Intersil's OFDM now stands as the sole candidate to be considered by the IEEE's 802.11 Working Group as the industry standard for 802.11g products. But the OFDM proposal must still be ratified by over 75 percent of the IEEE's .11g Task Force. The ratification vote could come as early as Thursday. After which, it would then go to the IEEE's larger 802.11 committee.

But Wednesday's vote wasn't a clear victory for Irvine, Calif.-based Intersil. If the proposal isn't ratified for the full membership, implementing an 802.11g specification standard could drag out indefinitely until more proposals can be resubmitted.

"If OFDM does not win tomorrow this could drag out," said Navin Sabharwal, vice president of residential and networking technologies at Allied Business Intelligence (ABI), an Oyster Bay, NY-based think tank.

A spokesman for Intersil declined to comment pending the outcome of tomorrow's vote.

What is clear, though, is that the vote dashes TI's hopes of being a technological leader in the field of high speed data transmission in the 2.4GHz spectrum -- an area where development activity has been running rampant. True, TI is already a leader in DSP and analog circuitry. But TI's Wireless Networking Business General Manager Mike Hogan was quoted as saying "our intent would be to support whatever standard is out there, but we would be hard-pressed to come up with a definitive availability date for the other proposal."

The politics of spectrum

The IEEE's voting was based principally on two factors. First, how well does the technology perform? And secondly, how well the technology complied with FCC regulations? But in knocking out TI, IEEE members may have been more focused on the latter, Sabharwal noted.

In terms of performance, Intersil's OFDM does offer more scaleability to bring data rates faster than 22 Mbps while TI claimed its proposal offered less interference and greater compatibility with existing technologies. (To be fair, they also contend PBCC is also capable of higher transmission speeds albeit their proposal was submitted to the IEEE using 22 Mbps for the standard.)

"I am not convinced that you can clearly prove definitively that either technology is superior. It really depends on which benchmarks you are looking at," Sabharwal explained.

"I think that the vote illustrates that at least some people conceptually prefer the idea of OFDM because it appears to be the way many technologies are going ... Ultimately there are more engineers out there who know the benefits of OFDM and have first-hand experience with it."

In fact, as Sabharwal explained, the IEEE's actions appear to be more politically motivated.

Last week, the FCC surprised many by unexpectedly relaxing its position of opposing OFDM-related technologies. The federal agency had resisted OFDM-related specs because it used up more of the precious spectrum space compared with other technologies known as direct sequencing spread spectrum (DSSS) systems. But all of the sudden, the FCC last week granted Wi-LAN Inc., a Canadian developer of OFDM technologies, waivers from those hefty regulations.

"With the FCC decision on Wi-LAN there is now less hesitance to vote for OFDM. While the FCC previously rejected OFDM they had never officially done so with PBCC. The TI camp previously could use this fact to bolster their support, but can no longer do so," Sabharwal said.

IEEE officials weren't immediately available.

Much of the reason for the heightened interest in 802.11g is related to the limitations of current 802.11b technology. Since the 802.11b specification was finalized by IEEE in 1999, many networking companies from Intel to Compaq have quickly adopted it -- only to find its theoretical transmission speeds of 11 Mbps a bit of a misnomer. Due to legacy synchronization issues, 802.11b only nets about 7 Mbps of throughput.

The IEEE is also working on other specifications such as .11e (for voice transmission and security) and .11a (which promises data rates of 54 Mbps). But 802.11g is expected to bring wireless streaming media capabilities to market the earliest.