Speaker:
Eylem Ekici
Ohio State Univerity
Columbus, OH, USA
http://www.ece.osu.edu/~ekici/

Date: Wednesday July 1, 2009
Time: 3:30 – 5:00 pm
Location: Wireless Intelligent Networks Center (WINC).

Abstract

Cognitive radio networks are emerging as solutions to alleviate the increasing demand for spectrum for unlicensed users and applications. While ISM band is ubiquitously accessible across the globe, the explosive growth in use of such devices forced the evaluation of new methods and approaches to increase the available bandwidth. The observation that significant portions of the licensed band is underutilized coupled with the advances in software defined radios that can adjust its parameters on-the-fly have lead to the notion of cognitive radios and networks formed by such devices.

In this talk, two relatively new concepts about the cognitive radio networks will be discussed. First, we will look at a collection of CR nodes forming ad hoc networks and question how the routing problem can be addressed. The main challenge here lies with the coordination of path formation and maintenance despite the variable nature of the CR channels. Existing solutions as well as new approaches to this problem will be explored. The second part of the talk is devoted to a new architecture which questions the basic assumption of primary users being oblivious to the presence of secondary users. Regarding the primary users as the owners of the property and the secondary users as potential temporary lease holders, we entertain the idea of finding solutions that can improve the primary user performance while granting right to secondary users to access the leased spectrum. Some potential solutions will be discussed and open research directions will be presented.

Biography

Eylem Ekici has received his BS and MS degrees in Computer Engineering from Bogazici University, Istanbul, Turkey, in 1997 and 1998, respectively. He received his Ph.D. degree in Electrical and Computer Engineering from Georgia Institute of Technology, Atlanta, GA, in 2002. Currently, he is an associate professor in the Department of Electrical and Computer Engineering of the Ohio State University, Columbus, OH. Dr. Ekici's current research interests include wireless sensor networks, cognitive radio networks, and vehicular communication systems, with a focus on routing and medium access control protocols, resource management, and analysis of network architectures and protocols.