MIMO (multiple input, multiple output) technology runs multiple data streams in a single channel to boost throughput to rates of up to 108M bps, which is double that of the maximum speeds of 802.11a or 802.11g. Some variant of MIMO will be at the heart of the upcoming IEEE 802.11n standard, but ratification of that standard isnt expected until the second half of 2006.
Leading the push for pre-standard MIMO is Airgo Networks Inc., a startup that launched its first MIMO chip set in 2003.
As is often the case with pre-standard wireless technology, the initial adopters of Airgos chip set were companies such as Linksys (a division of Cisco Systems Inc.) and Sohoware Inc., which traditionally serve small business and home users rather than enterprise customers.
But the tide is turning, according to Airgo officials, who said the company will announce a new line of chip sets and at least one large enterprise-level licensee within the next quarter.
"Theyre definitely very open to it now," said Greg Raleigh, CEO of Airgo in Palo Alto, Calif. "A year ago they were not so open. Our competitors have offered countermessages that have attenuated our basic point of view—the point of view is that theres nothing to lose by shipping the MIMO products before 802.11n."
Current Airgo chip sets may not be upgradeable to 802.11n, but they enhance the performance of existing IEEE standard equipment, Raleigh said.
"The good news is that this technology coexists with existing 802.11b/g/a systems," said Brad Noblet, director of technical services at Dartmouth College in Hanover, N.H. "Installing MIMO doesnt [render] obsolete existing systems."
On the client side, Samsung Electronics Ltd. earlier this month announced that it will use Airgo chip sets in upcoming versions of its X20 and X25 notebooks, which currently use the competing Centrino chip set from Intel Corp. (Airgo commissioned an independent test by Tolly Group, which showed that these notebooks delivered five times the throughput and up to ten times the coverage of Centrino-based notebooks even when connecting to a standard 802.11g access point that doesnt have any MIMO in it.)
The Samsung laptops will not be available in the United States, but Raleigh said that Airgo-enabled notebooks from U.S. licensees should hit the market in 2006.
Raleigh declined to name unannounced licensees, but enterprise-focused Wi-Fi companies have acknowledged pre-n plans.
WLAN (wireless LAN) hardware maker Trapeze Networks Inc. will unveil plans for pre-standard MIMO products within the next month. They will be targeted toward "specialized applications" and will work with the companys existing centralized switch and management software, according to officials at the Pleasanton, Calif., company.
Aruba Wireless Networks Inc. of Sunnyvale is considering Video54 Technologies Inc.s BeamFlex, which uses switched antenna technology to increase throughput and range and works in conjunction with other vendors silicon.
Officials at market leader Cisco Systems Inc. declined to comment on the companys MIMO plans other than to say that the company is "pursuing an aggressive next-generation wireless access point strategy, which includes the 802.11n opportunity."
Other WLAN veterans are adamant about waiting for a standard.
"We do not plan to release pre-standards gear, whether using MIMO or another chip set technology," said Anthony Bartolo, vice president and general manager of the wireless infrastructure division at Symbol Technologies Inc. in San Jose, Calif. "Deployment of pre-standardized 802.11n gear requires a lot of consideration due to proprietary hardware and system technologies. Users who installed the pre-n gear may find they may need to rip out and replace the gear."
For enterprise customers, the choice comes down to the immediate need for speed.
"I just moved my laptop from 802.11b to g and I have noticed a big difference, but that is a factor of five," said Jorge Abellas-Martin, CIO of Arnold Worldwide in Boston, who is an eWEEK corporate partner. "Going from 54 to 100 I dont think will make a big difference to the garden-variety user, so I would personally wait until a mature standard emerges."