“An Information-Theoretic Study of the Cognitive Radio Channel”

Abstract

With rapid deployment of various wireless services, the limited radio spectrum becomes increasing crowed. On the other hand, most allocated radio spectrum experiences low utilization. As an emerging technology to support dynamic spectrum access, cognitive radio allows the secondary users (unlicensed users) to opportunistically or concurrently access the frequency bands of primary users (licensed users), thus having a potential to enhance spectrum utilization efficiency. 

In this talk, we will start with a brief overview of the current research on cognitive radio. We next will focus on an information-theoretic study of the concurrent cognitive radio channel, in which two senders attempt to communicate with their respective receivers simultaneously through a common medium, and one of the senders has complete and a priori (non-causal) knowledge about the message being transmitted by the other. We will discuss a new coding scheme that collectively has advantages of cooperative coding, collaborative coding, and dirty paper coding. Achievable rate results in both discrete memoryless and Gaussian case, which are obtained by using this coding scheme, will be presented next.  A numerical example for the Gaussian case will also be provided to illustrate that the achievable rate results offer considerable improvements over some of existing results in the high-interference-gain regime.

Joint work with Jinhua Jiang (National University of Singapore).

Bio

Yan Xin received the Ph.D. degree in electrical engineering from University of Minnesota, Minneapolis, in 2003.  Since 2004, he has been with the Department of Electrical and Computer Engineering, National University of Singapore, Singapore, where he is now an assistant professor. His current research interests include cognitive radio, network information theory, and MIMO communication.  Dr. Xin was the co-recipient of the 2004 IEEE Marconi Paper Prize Award in wireless communications.