SAN JOSE, Calif. — WiMax won't grab the brass ring as the technology that defines fourth-generation cellular sys- tems. But it is likely to capture a healthy minority stake in that emerging sector, and it could help bring Internet ac- cess to a new generation of consumer devices.

That was the assessment that emerged from the annual gathering here of the Wireless Communications Association International (WCA), a lobbying group whose members generally promote WiMax. While proponents, including Intel Corp., have fueled plenty of hype about the broadband wireless technology, last week's confab made it clear that WiMax holds real, though limited, promise and faces several challenges.

Even WiMax proponents in the WCA admitted that Long Term Evolution (LTE), a follow-on to cellular's GSM standard, will command the lion's share of fourth-generation cellular systems. That's because the huge breadth of GSM service providers will be able to roll their subscribers over from today's wideband CDMA to LTE when the time comes. LTE is still being defined.

There are a whopping 122 commercial wideband-CDMA networks—with 70 million subscribers—operating in 55 countries and using 407 distinct handsets today, reported Jake MacLeod, chief technology officer of Bechtel Communications Inc. (Frederick, Md.). "There's a huge momentum for existing wireless services," said MacLeod, whose company builds public networks for carriers.

By contrast, no carriers have deployed the 802.16e mobile WiMax spec officially defined at last year's WCA meeting. That's because carriers decided they wanted to deploy a second-generation version of the spec supporting the same multiple-input, multiple-output (MIMO) antenna technology that will be used in LTE and in rival technology under development at Qualcomm Inc.

Systems for that version of WiMax won't be certified and available until late this year. In addition, the technology faces nagging spectrum debates that impede some uses. "We're moving the flag down the field, but not as far as we thought," said MacLeod.

MacLeod said carriers Sprint Nextel, startup Clearwire and Russia's Sistema have committed to WiMax, while Cingular and Vodafone are backing LTE. AT&T, BT and Verizon may use WiMax as an adjunct to their fiber-to-the-home deployments, and satellite broadcasters are considering WiMax as a back channel, he added.

Long term, "LTE will garner the market share advantage [in 4G cellular], but WiMax could grab a very significant portion of it--perhaps as much as 20 percent. That's a gargantuan market globally," said MacLeod, whose company has hundreds of active network deployments worldwide, including some of the largest cellular systems.

Given the delays, Sprint Nextel has scaled back 2007 spending plans on WiMax from $1 billion to "up to $800 million," said Philip Solis, a senior mobile analyst at ABI Research (Oyster Bay, N.Y.). "Systems and service providers wanted to make sure they got .16e right before it went out the door, and the result has been something of a mess."

"We will be demonstrating .16e around the end of the year to show our customers we have this capability, but real deployments are two to three years out for most customers," said Majed Sifri, chief executive of systems maker Redline Communications Inc. (Markham, Ontario).

Like most WiMax systems companies, Redline is focusing its 2007 business on deploying fixed-access systems using the 802.16d standard in developing countries as an alternative to digital subscriber lines. Nevertheless, Sifri said that "two-thirds of our engineers are now focused on .16e."