Wireless USB has arrived - at least in the form of demonstrations and a formal standard definition. But it won't end the ultra wide-band (UWB) wars, and the technology faces regulation problems - as well as implementation issues.

This week's announcements give some solidity to the ultra wideband world (UWB), where regulatory and standards-group issues have threatened to trap the technology on the drawing board. Some even predicted that UWB will get a world market through the influence of the ITU telecoms group, possibly as soon as December.

W USB is here
Version 1.0 of the Wireless USB standard was announced at the Wireless USB Developers Conference, by the Wireless USB promoter group which is backed by Intel and Microsoft. The group plans to have wireless USB as an option in PCs some time next year.

The basic technology for Wireless USB - a 480 Mbit/s UWB link - was shown by Alereon (which makes the physical layer or PHY) and Intel (which provides the media access control layer, or MAC). The demonstration made UWB look more practical than some previous ones: Alereon put its AL4400-EVB UWB evaluation kit on a PC Card module.

Will it end the UWB wars?
The arrival of UWB has done little to end hostilities in the UWB technology wars. Wireless USB will be based on the WiMedia flavour of UWB, but the rival DS-UWB from FreeScale is still out there.

The debate was just as strong at Wireless Connectivity event in London where, Freescale's DS-UWB version was very much in evidence. Freescale has beaten the others to silicon, and claims to have mini-PCI modules in production for $20. The company demonstrated 100 Mbit/s video across more than the claimed 20m distance - with Freescale pointing out that a waiver granted by the FCC would double its range.

"We can scale well," said Martin Rofheart, director of UWB operations at Freescale. "We can deliver 1 Mbit/s per mW of power, from 20 Mbit/s up to 1.6 Gbit/s."

Despite being early to market, Freescale can't hide the fact that the big industry gang is behind WiMedia - and the wireless USB standard. The UWB Forum has a long list of members, which contains so few large players compared to WiMedia's list), that most regard it as the "political wing" of Freescale.

Rofheart is sceptical about Wireless USB: "It will have to start over, because there is no metaphor for wireless in USB." With the recent endorsement of UWB by the Bluetooth SIG, Rofheart suggests that Wireless USB might be better off becoming a Bluetooth profile.

Enough people mention this possibility, to suggest that, at some point, Wireless USB and Bluetooth may collide. Bluetooth, with its already-existing security and applications, may even get to the market on UWB sooner than Wireless USB.

Wireless USB on Freescale?
In any case, Rofheart promises Wireless USB on the Freescale technology, using a "PHY-agnostic" Wireless USB created by Icron. It replaces a USB cable with a seamless wireless link, emulating the USB wire. In fact, it is so PHY agnostic, that it can be implemented on any wireless network, including Wi-Fi, according to Icron.

WiMedia vendors are not impressed. Jason Ellis of Staccato Communications warns: "Icron promises to spoof around USB, but it is not well optimised, and may impact other networks. Wireless USB is optimised for multiple networks and will consider its neighbours.

Issues for Wireless USB
The Wireless USB group acknowledges that there are issues to deal with, including "association". Users need to be sure they are connecting with the devices they think they are, and that strange devices are not joining in.

Bluetooth solves this with four-digit PIN codes, but there are reports that Wireless USB may use a traditional USB wire for the first time you pair your camera with your PC, which would then not be required whenever you use it again.

"There are three proposals," said Kursat Kimyacioglu, director of wireless business development at Philips. "Cables, near field communications and plugging in a flash memory module. There's a tendency in the Wireless USB camp to make the cable the basic solution. They want to preserve the look and feel of USB, and its ease of use."

What about the regulations?
It's still not at all clear that Wireless USB-equipped PCs will be available outside the US. UWB proponents at the WiCon event in London were predicting that by December, the technology might get past the regulators. Currently, outside the US, but UWB is still illegal except for research projects and demonstrations.

"Most bodies are looking to the ITU," said Kimyacioglu, referring to an task group of the telecoms standards maker, which is due to form ITU policy on UWB later this year. "I think there will be a decision in December, and countries will follow that decision."

Although the ITU has no regulatory powers, its recommendations carry a lot of weight. "We're hopeful that we may see waivers in major Asian countries," said Martin Rofheart of Freescale, "and approvals in 2006."

In the long term, he believes in a big change in spectrum management. "We are moving from a property school of spectrum management to a technology school," he says.