CS Colloquia: Next Generation Dynamic Spectrum Systems

Title: Next Generation Dynamic Spectrum SystemsSpeaker: Prof. Heather Zheng(UCSB)ABSTRACT:
Today's static spectrum assignment policy has led to a critical spectrum
shortage. While innovative wireless networks such as WiMAX are denied
from spectrum access, the majority of existing networks use only 10-15%
of their assigned spectrum. To reuse "wasted" spectrum, the recent
proposal on dynamic spectrum access allows unlicensed (secondary) users
to opportunistically utilize unused licensed spectrum on a
non-interfering basis. This "creates" new capacity and commercial value
from existing under-utilized spectrum.While it shows great promise, the technology underlying dynamic spectrum
systems is still in its infancy. Issues in wireless communications and
networking, once addressed in the context of fixed spectrum assignment,
offer new research challenges in the realm of dynamic spectrum systems.
In this talk, we describe some existing and on-going efforts on
dynamic spectrum systems. We begin by describing distributed algorithms
for secondary users to access spectrum fairly and efficiently. We
introduce (1) a distributed coordination approach where devices
coordinate to adapt spectrum assignment over topology variations, and
(2) a light-weight rule-based solution that requires minimum
communication overhead. We then present a dynamic spectrum auction
framework that addresses the impact of economic issues. We conclude by
summarizing this work in context, and discussing current and future
directions in combining these results with higher layer mechanisms, and
applying cross-layer design to produce an end-to-end programmable and
adaptive network.Additional information about this research can be found at
http://link.cs.ucsb.edu.BIO:
Since August 2005, Heather Zheng has been an assistant professor at
Department of Computer Science, University of California, Santa Barbara.
Her research area includes wireless networking and communications, and
multimedia computing. She currently focuses on Cognitive Radios and
dynamic spectrum networks. Her research on Cognitive Radios was selected
as one of the 10 Emerging Technologies of 2006 by MIT Technology Review
Magazine, and the Best Student Paper in IEEE DySPAN 2007. Dr. Zheng was
named as the MIT Technology Review's Top 35 Innovators under the age of
35 in 2005. She also received 2006 World Technology Award (top 5 in
communication), 2002 Bell-Labs President's Gold Award, 1998-99 George
Harhalakis Outstanding Graduate Student Award from University of
Maryland, College Park. Dr. Zheng received her Ph.D. from University of
Maryland, College Park in 1999 and then joined wireless research lab,
Bell-Labs, Lucent Technologies. She then moved to Microsoft Research
Asia as a project lead in March 2004 and later joined UCSB.

Location: Seaver Science Library (SSL) - 150

Audiences: Everyone Is Invited

Contact: CS Colloquia