Ultra-Wideband will change your digital home

Wireless USB only one way wireless tech will make difference

TODO alt text

Back in February, the EU passed its legislation outlining the authorised use of the radio spectrum for ultra-wideband technology - and 21 August is the deadline for member states to pass it into law. Ultra-Wideband (UWB) will mean a lot for proponents of the digital home.

It'll mean more devices can be connected without cables - meaning we could see the end of the mass of cables behind your TV and hi-fi with pictures and sound streamed wirelessly between kit. UWB uses relatively low power to transmit data across a large amount of radio bandwidth - at least 500MHz, but potentially several gigahertz - simultaneously.

In the UK, telecommunications regulator Ofcom has already committed to following the EU's lead. It allows the technology under the Wireless Telegraphy (Exemption) Regulations, which will soon become law. The change in the law marks the end of a long process which finally brings Europe into line with US legislation allowing unlicensed use of the frequency ranges between 3.1 and 10.6GHz for UWB.

The principle is very similar to MIMO (Multiple In, Multiple Out) wireless networking adaptors. Many channels within a radio frequency range are used to transmit data in parallel, increasing transfer speeds and reducing the chances of interference. Current standards for Ultra-Wideband have been developed and promoted by the WiMedia Alliance .

C-WUSB is on its way

There are already several products available elsewhere in the world - like Philips' wireless HDMI adaptor - which use UWB transceivers and will be legally available in Europe for the first time after the 21st.

The most important application of UWB, though, is Certified Wireless USB (C-WUSB). The 'Certified' prefix has been adopted to differentiate C-WUSB kit from existing Wireless USB adaptors. These tend to refer to 802.11 WiFi transceivers.

C-WUSB, though, is the next progression of good old USB. It transfers data at USB 2.0 speeds (480Mbps) at ranges of up to three metres, slowing to 110Mbps at up to 10 metres. Like USB, a C-WUSB hub can support up to 127 devices at any one time. At CES this year in Las Vegas, the USB Forum was out in force, demonstrating prototype cameras and printers with built-in C-WUSB transferring images at full USB 2.0 speeds.

Right now, there are notebooks coming from Dell and Lenovo with built-in C-WUSB hubs, while D-Link and IOGEAR both have hubs and adaptors which sport the official logos. All should be available in the Autumn.

Belkin, in the meantime, has a wireless USB hub and adaptor kit out in the US which will be C-WUSB compatible - although possibly not supporting official certification. It'll be out in Europe in time for Christmas. Hubs and adaptors will be a relatively pricey £200 per pair initially, while pricing for the notebooks hasn't yet been revealed.

Trouble ahead

Over the next few weeks there will be many announcements about Wireless USB kit, and possibly some from the Bluetooth SIG regarding version 3 of the Bluetooth specification. Intreguingly, this will also use UWB to achieve faster data rates. There are still potential pitfalls for UWB technology, though. One of the key components of the EU decision on UWB is that UWB equipment "does not cause or contribute to undue interference to any wireless telegraphy".

Some commentators, including Hutchinson 3G and the UK Maritime and Coastguard Agency have voiced worries that the current regulations are vague as to the nature of "undue interference". The action Ofcom will bring to manufacturers straying from the UWB guidelines is also uncertain. Given the amount of low cost C-WUSB kit about to hit our shores, these could well be valid concerns.

It's unlikely that disaster is looming, though. Rather, we're about to enter the truly wireless age where putting your camera on your desk without a cradle or cable will immediately instigate WUSB transfers of pictures. High def movies and music will be able to be pumped around from PC to TV without the need for a WiFi network. The future is, as they say, almost here.