Predavanje: Cognitive Radio Games

Cognitive Radio Games

K. J. Ray Liu

Electrical and Computer Engineering Department

University of Maryland, College Park

Cognitive radio is an intelligent wireless communication system that is aware of its surrounding environment and can adaptively change its operating parameters based on the interactions with the environment and users. With cognitive radio technology, future wireless devices are envisioned to be able to sense and analyze their surrounding environment and user conditions, learn from the environmental variations, and adapt their operating parameters to achieve highly reliable communications and efficient utilization of the spectrum resources. In a cognitive network, users are intelligent and have the ability to observe, learn, and act to optimize their performance. Since they generally belong to different authorities and pursue different goals, fully cooperative behaviors cannot be taken for granted. Instead, rational users will only cooperate with others when cooperation can benefit them, e.g. improving their own performance. Therefore, a key problem in cognitive networks is how to stimulate cooperation among rational users and how to defend against intelligent attackers. To address the interactions of the dynamics among conditions, resources, environments, and users, game theory has naturally become an important emerging tool that is ideal and essential in studying, modeling, and analyzing the cognitive interaction process. There is of course no surprise since game theory has been a core tool in the study of human economics and business models, in particular in understanding of cooperation, interaction, and conflict, via which strategies and mechanisms can be developed to offer flexible and adaptable solutions. In a certain sense, what is taking place in cognitive communications and networking can be viewed as a kind of information games, where optimal policies, strategies, protocols are developed by the information obtained by users through interaction, cooperation, or competition of communication/networking devices, contrasting to economic and financial games being considered in human society. Not only traditional games can be leveraged to apply to various networking scenarios, but can also new games be developed since wireless communications is interference-limited instead of quantity-limited as the case for most economic models. Therefore we are seeing the new era of information games emerging and unfolding. In this talk, some recent advances on the use game theoretical frameworks for cognitive radios in improving robustness and security will be discussed and illustrated, as well as some future directions.

Biography

Dr. K. J. Ray Liu was named a Distinguished Scholar-Teacher of University of Maryland in 2007, where he is Christine Kim Eminent Professor in Information Technology. He leads the Maryland Signals and Information Group conducting research encompassing broad aspects of wireless communications and networking, information forensics and security, multimedia signal processing, and biomedical engineering. Dr. Liu is the recipient of numerous honors and awards including IEEE Signal Processing Society Technical Achievement Award. A Fellow of the IEEE and AAAS, he is recognized by Thomson Reuters as an ISI Highly Cited Researcher. Dr. Liu is President-Elect of IEEE Signal Processing Society. He was the Editor-in-Chief of IEEE Signal Processing Magazine and the founding Editor-in-Chief of EURASIP Journal on Advances in Signal Processing. Dr. Liu also received various research and teaching recognitions from the University of Maryland, including Poole and Kent Senior Faculty Teaching Award and Outstanding Faculty Research Award, both from A. James Clark School of Engineering; and Invention of the Year Award from Office of Technology Commercialization.