For a while there, it seemed like Mobile WiMAX was the greatest thing since 3G — and maybe greater than 3G. In December 2005, the IEEE ratified the 802.16e standard, which is the basis for Mobile WiMAX, and several vendors and service providers immediately hopped on board the hype express. The understanding among many of them was that they would skip Fixed WiMAX, despite the WiMAX Forum's certification of the first Fixed WiMAX products in January, and wait for the full mobility features and more robust performance of Mobile WiMAX.

The appearance of Mobile WiMAX firms last month at Wireless 2006, the mobile industry's biggest U.S. trade show, seemed to reinforce the increasing belief that Mobile WiMAX could be a viable alternative to 3G or other future mobile broadband generations, and would eclipse Fixed WiMAX (Telephony even said so in our last issue: April 24, page 26). Meanwhile, the expectation has been that the Mobile WiMAX certification process will begin late this year and that commercial products will be available some time next year.

That schedule hasn't changed, according to the WiMAX Forum, but recently it has become more apparent that Fixed WiMAX and broadband fixed wireless in general — including high-frequency LMDS — won't be so quietly sidelined. Increasing awareness of the need for viable broadband backhaul options and the emergence of fixed-but-portable access products and service strategies have the companies that have invested heavily in fixed technology reminding the industry and potential customers of its benefits.

“One of our bets is that whatever happens, Fixed WiMAX will remain a big part of the overall broadband wireless equation,” said Robert Fitzgerald, CEO of Proxim Wireless, in his keynote speech two weeks ago at the Broadband Wireless World conference in Las Vegas. Fitzgerald pointed to backhaul as a huge Fixed WiMAX market opportunity that will continue to grow, regardless of what kind of broadband access methods dominate.

That tune also was sung by service providers such as XO Communications, which recently launched its Nextlink subsidiary to attack the backhaul, enterprise and government markets. Though Nextlink's technology resides in the LMDS spectrum of 28 GHz to 31 GHz, and is not the subject of any current or near-future WiMAX certification profiles, Tom Cady, president of Nextlink, said fixed wireless as a whole discipline is back with a vengeance.

“Backhaul was not even in the vocabulary back in 1999,” said Cady, referring to an earlier, less successful broadband era. “Now, it's the most visible usage of fixed wireless spectrum. Now, the technology is better, there are more choices and more practical uses for it.”

Nextlink officials said that over the next few years, the average cellular tower will require an average of 30 Mb/s backhaul capacity to support the wealth of mobile data and content applications that are just beginning to surge in popularity.

Although backhaul opportunities make service providers enamored of fixed wireless, vendors like Aperto Networks and TeleCIS Wireless say the emergence of more portable fixed wireless solutions will do their part to win over end users well before alternatives like Mobile WiMAX are available.

“We've maintained that the Fixed WiMAX market is a huge market,” said Manish Gupta, vice president of marketing and alliances for Aperto, which already has landed several Fixed WiMAX contracts worldwide. Regarding the market for Mobile WiMAX with full mobility, Gupta said, “3G is already here. Mobile WiMAX will offer high-speed data and mobility, but what applications will require 5 Mb/s downstream while traveling at 70 miles per hour? What is the killer app for that? I don't think anyone knows yet.”

Gupta said Aperto will eventually produce a Mobile WiMAX system because the link budget and other benefits of Mobile WiMAX are hard to dispute. However, for companies like Aperto and TeleCIS, there's more viability in an interim “fixed/portable” market — essentially Fixed WiMAX products that take advantage of the portable-scale chips, customer premises equipment and capabilities.

TeleCIS just announced a dime-sized fixed-portable chip to fit the connectivity budget of laptop manufacturers. “There was this belief that you needed something based on 802.16e for WiMAX to get into laptops,” said Dave Sumi, vice president of marketing for TeleCIS. “That's just not true.”

Though it sounds like there could be a rift developing between the Fixed WiMAX and Mobile WiMAX camps, Jeff Orr, director of marketing for the WiMAX Forum, said there's no in-fighting among forum members about the two WiMAX flavors. “This is all normal behavior and part of the technology lifecycle,” he said. “I'm glad we're at a point where two different opportunities are being approached, both with technology from within the WiMAX industry.”

Monica Paolini, president of Senza Fili Consulting, said there's little reason to believe an intense competition will develop between Fixed WiMAX and Mobile WiMAX. “My impression is that the side that feels more vulnerable is the one likely to shout the most. If you look at the certification profiles, the only band where there is true competition between the two is 3.5 GHz TDD.” Paolini also pointed out that the 3.5 GHz band has limited potential to support mobility.

Meanwhile, there are still some who doubt the resurgence of fixed wireless and Fixed WiMAX. As part of its recent acquisition of TelCove, Level 3 acquired some LMDS spectrum, but Brian Washburn, principal analyst for network services at Current Analysis, said Level 3 should sell that spectrum (see related story on page 13). “The last thing in the world that Level 3 needs right now is some sort of a blue sky big investment that may not pay off until well down the road,” he said. “That's not what their investors want to see.”