London -- The Bluetooth Special Interest Group's choice last week of the WiMedia Alliance's ultrawideband multiband orthogonal frequency-division multiplexing UWB specification for its high-speed future seemed almost inevitable.

However, if the alliance thought that its ultrawideband announcement would trigger an outbreak of peace in the fractious world of UWB, it will probably be disappointed.

Though the backers of the rival direct-sequence UWB--mainly key UWB Forum members Freescale Semiconductor and Motorola--are likely to be disappointed, they are not about to raise a white flag.

Mike Foley, executive director of the Bluetooth SIG, said, "Having considered the UWB technology options, the decision ultimately came down to what our members want, which is to leverage their current investments in both UWB and Bluetooth technologies and meet the high-speed demands of their customers." He added, "By working closely with the WiMedia Alliance to create the next version of Bluetooth technology, we will enable our members to do just that."

Foley denied suggestions that the group's decision was in any way forced by the independent decision in February of CSR plc to adopt the WiMedia Alliance's technology for future product development. CSR is the leading supplier and developer of Bluetooth chips. "Our members overwhelmingly told us WiMedia was the technology they wanted to see in the next Bluetooth specification," he said.

The Bluetooth SIG and the alliance will now develop jointly a high-speed, high-data-rate Bluetooth solution that uses the unlicensed radio spectrum above 6 GHz. "The plan is to have an initial specification completed by the first quarter of 2007," Foley said. "Then we will need to have a test and prototyping phase for the implementations, followed by multiple test events to ensure interoperability. This will take another six months or so, at least." Actual products incorporating devices meeting the revised specifications are not expected to ship until 2008.

Foley said the target is for the high-speed devices to have the same power budget as existing Bluetooth parts and that "the sweet spot in terms of throughput will be about 100 Mbits/second at the same range of about 10 meters as we have now for Bluetooth."

Foley told EE Times that theSIG chose the WiMedia Alliance's version of UWB for a variety of reasons. "It was a collection of features, and in particular the momentum behind products conforming to the WiMedia Alliance's version," he said. "We are hoping the UWB Forum will continue to work with us, though I accept [that] they would need to change their technology."

He noted that about 500 million Bluetooth devices are likely to be shipped this year, and that by 2008 the number is likely to increase to 1 billion. "You just don't walk away from that kind of market."

In response, Martin Rofheart, director of ultrawideband operations at Freescale, told EE Times that the company and the UWB Forum members have no intention of giving up on their spec. "We are unperturbed and, more significantly, unaffected by the SIG announcement. We will continue to execute on our plan and Freescale remains the only semiconductor company actually shipping silicon for UWB."

Rofheart added, "The personal-area network scene is driven not by Bluetooth but by cable-free USB, which leverages the over 1 billion USB 2.0 devices out there and uses DS-UWB technology for true wireless USB connection."

Last week's announcement, Rofheart maintained, "is a distraction for the WiMedia and Bluetooth development community. They are now required to make significant modifications to their technology and strategies. In any case, markets are not driven by technical announcements, but by technological achievements.

"There are no high-rate Bluetooth applications today," Rofheart said, "nor are there any slated for the near term, which makes [it] an interesting technology to watch over the coming years. When there are well-defined applications that could benefit from our UWB technology in the Bluetooth area, we will pursue them."

Foley said, "This move, in particular the choice of using the higher-band 6- to 9-GHz frequency range, should answer concerns voiced by regulatory bodies in both Europe and Asia."

In addition to regulatory concerns, the Bluetooth SIG also needed to make sure that the UWB technology was compatible with Bluetooth radios and maintain the core attributes of Bluetooth wireless technology. Those advantages include low power, low cost, ad hoc networking, built-in security features and the ability to integrate into mobile devices.