题目：Cooperative Spectrum Sensing and Multihop Relaying in Cognitive Radio Networks
Abstract: There exist two well-known cooperation mechanisms in cognitive radio networks (CRNs): the cooperation among secondary users for collaborative spectrum sensing, and the cooperation between primary and secondary users for cooperative relaying. In this talk, I will report our recent results on cooperative spectrum sensing and multihop relaying in CRNs. Deviated from the existing research we consider a scenario in which each secondary user has the freedom to decide whether or not to participate in cooperative spectrum sensing. Such a mechanism can conserve the energy for spectrum sensing at a risk of scarifying the spectrum sensing performance. We will address the following two questions based on evolutionary game and coalitional game: “which action (contributing to spectrum sensing or not) to take?” and “which channel to sense?” In cooperative multihop relaying, we will discuss a cooperation framework that considers spectrum sharing in both the time and the frequency domain, allowing relays to forward the primary traffic and to send their secondary traffic at the same time without interfering with the primary users. Within this framework, the multi-hop relay selection problem is formulated as a network formation game, in which the multi-hop relay path is computed via performing the primary player’s strategies in the form of link operations. The performance validation of our design will also be reported.
Short bio:Xiuzhen Cheng received her MS and PhD degrees in computer science from the University of Minnesota — Twin Cities, in 2000 and 2002, respectively. She is a professor at the Department of Computer Science, The George Washington University, Washington DC. Her current research interests focus on cognitive radio networks, wireless and mobile security, mobile handset networking systems (mobile health and safety), wireless and mobile computing, sensor networking, and algorithm design and analysis. She has served on the editorial boards of several technical journals (e.g. IEEE Transactions on Parallel and Distributed Systems, IEEE Wireless Communications) and the technical program committees of various professional conferences/workshops (e.g. IEEE INFOCOM, IEEE ICDCS, IEEE ICC, IEEE/ACM IWQoS). She also has chaired several international conferences (e.g. IEEE CNS, WASA). Xiuzhen worked as a program director for the US National Science Foundation (NSF) from April to October in 2006 (full time), and from April 2008 to May 2010 (part time). She received five best paper awards (IEEE MASS, IEEE Globecom, ACM CRAB, ACM ICUMC, WASA). She is a senior member of IEEE and a member of ACM.