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Colloquium - Lansford

White Spaces and Cognitive Radio: Turning Beachfront Spectrum into Timeshares
Cambridge Silicon Radio

For over 75 years, spectrum policy has largely been developed around allocating specific frequencies for specific types of usage, with strict controls on spatial and temporal occupancy. While these fixed allocations served the industry well for many decades, we are running into capacity limitations as the popularity of cellular and short range technologies such as Wi-Fi and Bluetooth dramatically accelerate. An obvious solution is better spectrum reuse; if a frequency band is not being used in a given location (or at a given time), regulators could allow reuse of the spectrum by another technology as long as does not cause "harmful interference." The initial spectrum sharing policies embodied in the FCC's Part 15 in the ISM bands were so successful that many groups developing these technologies are pushing for even more aggressive spectrum reuse by operating in unused portions of the UHF televisions bands. Other technologies such as ultrawideband are an "underlay" that is intended to operate below operational signal levels of incumbents. In both cases, these attempts to reuse spectrum have created a firestorm of controversy because incumbents and new users see "harmful interference" very differently. This presentation describes some of the current industry activities that are bringing these new methods of spectrum reuse to market, some of the regulatory issues being debated, and the challenges (as well as opportunities) that lie ahead.

Dr. Jim Lansford is a Standards Architect at Cambridge Silicon Radio (CSR), responsible for Wi-Fi standards and strategy. Prior to CSR, he was Chief Technical Officer of Alereon, an ultrawideband radio company. He is heavily involved in a number of standards, trade group and regulatory activities; he was formerly the co-chair of 802.15.3a (high speed UWB) as well as former chair of 802.19 (Wireless Coexistence Technical Advisory Group) within IEEE 802, and was also a significant contributor to 802.15.2 and 802.11g. He was also one of the developers of Adaptive Frequency Hopping for Bluetooth and led Alereon's UWB cognitive radio development.

In addition to his experience with CSR, Intel, Harris, NSA and three previous startups, Dr. Lansford has served on the teaching and/or research faculty of Georgia Tech, the University of Colorado at Colorado Springs, and Oklahoma State University. He has also served as a Visiting Associate Professor of Electrical Engineering at Texas State University in San Marcos, Texas. Dr. Lansford is an ABET Program Evaluator, a Senior Member of the IEEE, and has certification as a Wireless Communications Engineering Technology (WCET) professional.

Hosted by Timothy Brown.
Sponsored by the Interdisciplinary Telecommunications Program.

Department of Computer Science
University of Colorado Boulder
Boulder, CO 80309-0430 USA
May 5, 2012 (14:13)