After long delays, Intel will finally join the rest of the world of Wi-Fi silicon on Thursday, with a tri-mode chipset that handles 802.11a, b and g communications, according to sources familiar with the announcement.

With a chipset that includes IEEE 802.11a, b and g technology, a notebook PC can continue to connect to corporate wireless LANs without a hardware upgrade even if the enterprise migrates to a new infrastructure. Competitors such as Atheros, Broadcom and Texas Instruments have had tri-mode silicon for some time, prompting comments that Intel is hopelessly lagging the rest of the field, bringing out a combination 802.11b/g chipset earlier this year.

Intel spokeswoman Amy Martin declined to comment, but the company last week sent out an e-mail invitation to a webcast "to introduce its latest wireless technology for Intel Centrino notebooks."

"It really will mark the time that Intel's caught up," said Mike Feibus, an analyst at TechKnowledge Strategies, in Arizona. Intel's size makes it less agile than smaller competitors such as Broadcom, Atheros Texas Instruments, some analysts said.

In addition, Intel is very careful because it has so much invested in the Centrino brand, said Linley Group analyst Bob Wheeler. "They are extremely rigorous in terms of testing, primarily for compatibility but also making sure that they are complying with all the appropriate specs," Wheeler said.

The 802.11b and g technologies use radio spectrum around 2.4GHz to deliver data at a rate of 11 Mbit/s and 54 Mbit/s respectively. The less common 802.11a variant, also with a 54 Mbit/s rate, uses spectrum around 5GHz and can be used on more channels simultaneously. Also, there is less interference in the 5GHz band.

Despite a slow start, 802.11a is expected to begin gaining in popularity now (see 802.11a is back form the dead) as 802.11b and g networks get more heavily loaded with users, analysts said. The 2.4GHz technologies only allow for three channels to be used simultaneously. The number of channels on 802.11a varies by country but is generally more; it supports 24 in the US. That can make a difference in offices and crowded meeting rooms, Feibus said. Another emerging application for 802.11a is in wireless home entertainment systems.

Intel's Centrino marketing also should help drive adoption of tri-mode technology, said Will Strauss, principal analyst at Forward Concepts, in Arizona. But he believes most users, especially consumers, are happy with 802.11b/g for now. Demand for 802.11a will not suddenly soar, he said.

"We will see increasing demand ... but it's not going to be a hockey stick," Strauss said.

Another analyst said tri-mode has a big future, at least in the business market. "We'll see the enterprise products go to a/b/g probably almost exclusively by the first or second quarter of next year, if not sooner than that," said Abner Germanow, at IDC.

Users speak: A number of users are already adopting 802.11a for its better performance, and for migration from early 802.11b systems (read 802.11a - the users speak and The growing pains of a Wi-Fi pioneer).

Do you want 802.11a? Join our forum and tell us if and when you plan to use 5GHz Wi-Fi.