Ultra Wide Band

ULTRA WIDE BAND (UWB) COLLOQUIUM - Tuesday 23 July 2002

The Radiocommunications Agency sponsored a one-day colloquium on UWB technology which was held at the IEE headquarters in London. This event presented the state of the art in UWB and its potential applications. The afternoon session addressed implementation and regulation issues. An Open Forum session allowed questions to be put to the speakers. A summary of the issues raised is given below.

The event was cosponsored by the IEEE UK&RI Communications Chapter and was also supported by the IEE.

Background

On February 14, 2002, the Federal Communications Commission (FCC) issued a First Report and Order for UWB technology, which authorizes the commercial deployment of UWB technology. The possibility of UWB use within Europe has been addressed through a workshop organised by CEPT which was held in March 2001.

UWB devices operate by employing very narrow or short duration pulses that result in very large or wideband transmission bandwidths. UWB devices are designed to operate in spectrum occupied by existing radio services thereby creating the potential for more efficient use of the radio spectrum. The impulsive nature of UWB emissions and the resultant spectral characteristics have caused concerns about the compatibility of these signals with existing radio systems. The effective introduction of licence-exempt UWB devices across all frequency bands needs to be assessed carefully if disruption to existing services is to be avoided. It is suggested that foliage attenuation, absorptive soil, loss due to walls, people and structures, as well as other physical obstructions limit the amount of aggregation so that propagation exponents of 3.25 to 4 , as opposed to 2 for free space, should be used.

The range of UWB devices cited by the presenters at this colloquium was short (around 10m), with 30m being ideal. Power output is in the 40 - 80 mW range, rising to over 150 mW for high bit rates. Bit rates in the order of 100 Mb/s and above are the goal. Since there is no Rayleigh fading, it is possible to reduce the link budget by 20 - 30 dB.

The FCC has set extremely conservative emission limits for their UWB trial to protect Government-operated, safety-of-life and commercial radio systems from harmful interference. These limits are set out in FCC 02-48. A UK study was recently completed, Ultra Wide Band (UWB) Compatibility - Final Report (Aegis Systems Ltd, January 2002) which reviewed published work to date and set out possible areas of future study.

Three main areas of UWB application are: (a) imaging systems including Ground Penetrating Radars (GPRs), through-wall surveillance and medical imaging devices; (b) vehicular radar systems and (c) communications and measurement systems.

Programme:

(Click on the title to view the presentation in Adobe PDF format)

For further information:

Research and Coexistance of UWB: Trevor Clarkson
Trevor.Clarkson@ra.gsi.gov.uk

UWB T&D licensing and devices: Bob Barron
Bob.Barron@ra.gsi.gov.uk

Images from the Colloquium:

Trevor Clarkson (RA) Chairman

Panel Session (L-R):
Bob Barron (RA), Paul Withington (Time Domain), Sigurd Bolt Sørensen (ETSI), Soeren Hess (ECO), Chris Walden (Sony), Ewan Frazer (Thales), Steve Rowe (Siemens) and Trevor Clarkson (RA).

Not shown: Domenico Porcino (Philips), Jim Cohen (Jodrell Bank Observatory), Bharat Dhudia (RA).

Any enquiries can be made by e-mailing trevor.clarkson@ra.gsi.gov.uk

Or in writing to:

Professor Trevor Clarkson
Head of Engineering & Research Unit
9G/6A
Radiocommunications Agency
Wyndham House
189 Marsh Wall
London
E14 9SX

Telephone: 020 7211 0043