| Abstract: | Non-cooperative behaviors in communication networks can significantly adversely affect the entire network. Recently, researchers have begun to study such non-cooperative communication systems within a game theory framework and strive to engineer the system to prevent performance degradation under non-cooperative behaviors. The WWAN/WLAN two-hop-relay system described in [1] integrates two types of wireless technologies to improve wireless access throughput and coverage. The relay nodes in the two-hop-relay system can be wireless relay routers deployed by wireless service providers, or dual-mode users who voluntarily relay traffic for other users. However, it is reasonable to assume that all dual-mode terminals are selfish and are not willing to relay for other users without an incentive. In this paper, we will use the basic concepts of game theory, especially the concept of the Nash Equilibrium, to design our scheduling algorithms. Several scheduling algorithms, including the maximum rate C/I scheduler, the proportional fair scheduler, and the round robin scheduler, are examined to understand performance while operating under the assumption that all users are selfish. Under the C/I scheduler or the proportional fair scheduler, Nash Equilibriums exist at the operating points where no user will relay for other users—an undesirable situation. Under the round robin scheduler, selfish users are indifferent on relaying voluntarily or not relaying. Therefore, we are inspired to design a novel incentive scheduler. By applying the proposed incentive scheduler, all selfish users relay cooperatively at the Nash Equilibrium. Hung-yu Wei received a B.S. degree in electrical engineering from National Taiwan University in 1999. He received an M.S. and a Ph.D. degree in electrical engineering from Columbia University in 2001 and 2005 respectively. He is currently an assistant professor at Department of Electrical Engineering, National Taiwan University. His research interests are in cross-layer design issues of wireless mesh networks, and integration of mobile ad hoc networks with cellular networks. Richard D. Gitlin has more than 35 years of experience and leadership in the communications and networking fields. He is currently President of Innovatia Networks, a startup wireless company. Previously he was Vice President, Technology of NEC Laboratories America, Inc. and before assuming this position he was Visiting Professor of Electrical Engineering at Columbia University. After receiving his doctorate in electrical engineering from Columbia, he was with Lucent Technologies for more than thirty-two years, where he held several senior executive positions. He was the Chief Technical Officer and Vice President of R&D, of the Data Networking Systems Business Unit, and Senior Vice President for Communication Sciences Research at Bell Labs, Lucent Technologies where he managed and led research in wireless systems, broadband and optical networking, multimedia communications, and access technologies. He is the co-recipient of three prize paper awards including the 1995 IEEE Communications Society's Steven O. Rice Award, the 1994 IEEE Communications Society's Frederick Ellersick Award, and the 1982 Bell System Technical Journal Award. He is a co-winner of the 2005 Thomas Alva Edison patent award. Dr. Gitlin is the co-author of the text Data Communications Principles, more than 95 technical papers, numerous conference papers and keynote presentations. He holds 43 patents in the area of data communications, digital signal processing, wireless systems, and broadband networking. He is a member of the National Academy of Engineering, a Fellow of the IEEE, and is also an AT&T Bell Laboratories Fellow. Since May 2002, he has served on the Board of Directors of PCTEL [NASDAQ; PCTI], a wireless networking company. |
