May 2004

University of Southern California

Experts see ultrawideband local area networks and position locaters likely within three years

Survey finds technical challenges difficult but solvable

As part of his plenary address to an international conference on Ultrawideband technology now being held in Kyoto, Japan, University of Southern California UWB pioneer Robert Scholtz made public preliminary results from a wide-ranging survey on this question he made of more than 75 academics, business, and government experts in the field.

"The survey is continuing, and I expect and hope that more experts will participate," Scholtz said, "But I believe these initial results are an accurate reflection of what those best situation to know believe is the state of the art. These people not only know what UWB can do, but what it must do to successfully compete against alternatives already in the market."

Scholtz asked whether five possible applications would be viable business applications within the next 3 years, on a scale ranging from 10 ("a sure money maker") through 6 ("competitive in the market") down to 1 ("a good way to lose money.")

The group found that position locating devices (rangefinding systems able to determine the distance to remote objects) were the most likely to be commercial within 3 years, with a average score of 6.8.

High-speed local area networks, competing in applications like Apple's Airport utility, but with much higher transfer rates, were second, at 6.7, followed by imaging through materials (6.3); radio frequency tags (5.9) and intrusion alarms.

Scholtz also asked which of the two alternative competing systems, DS Impulse or OFDM now being evaluated by an IEEE standards group (IEEE 802.15), was superior. In this, the split was 42-58, with OFDM (being developed by Intel and Texas Instruments) receiving a plurality, but Motorola-identified DS hardly out of the running.

Scholtz also asked the group to grade the difficulty of pending challenges building various hardware elements for UWB systems on a scale from 1 (impossible) to 10 (easy. (While UWB uses conventional radio signals, most of the conventional design procedures both for chips and for broadcast antennas need drastic revisions to function).

Most of these challenges clustered around the 6 (possible now with effort), including a high quality full band antenna (5.6); a Local Area Network design (5.2); a unitary full-band transmitter (5.5); a 500 Mhz all-digital receiver (6.0), and a hybrid, analog-digital full band receiver (5.5).

The experts rate another desirable element, an all-digital full frequency receiver was rated as by far the most difficult problem. (3.9).

The group included 28 professors, 20 advanced students; 11 government specialists and 15 industry representatives, plus one anonymous correspondent, most from North America and Asia, but some from Europe and other areas.

Dr. Scholtz is a communications specialist who holds the Fred H. Cole chair at the USC Viterbi School of Engineering's department of electrical engineering and directs the Schools UltRa lab, a leading world center in UWB research. His work both theoretical and practical over the past decade has been widely recognized as central in the field.

Unlike conventional radio, which uses a carrier wave that is confined to a small frequency range of the radio spectrum, UWB sends out pulses that are recognizable precisely because they are spread across a huge range of the frequency spectrum. The technology originated in radar - what was called "baseband" radar - but related research showed possibilities for signaling.

The Federal Communications Commission after extensive consideration whether devices using the technology might interfere with broadcast media and the Global Positioning System, approved UWB for unlicensed use under strict power limitations for a large portion of the radio spectrum in a decision published in May, 2002. No commercial applications of this technology are yet generally available.








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