Cooperative and Competitive Coalitions in Wireless Interference Channels

SPEAKER: Dr. Lalitha Sankar, Postdoctoral Fellow, Princeton UniversityABSTRACT: Cooperation in multi-terminal networks can be induced in many ways. In this talk we investigate the formation of cooperative coalitions among rational users (transmit-receive links) in a K-link interference channel (IC) using coalitional game theory. Modeling the rate achieved by a user as its utility, we show that the stable coalition structure, i.e., set of coalitions from which users have no incentives to defect, depends on the manner in which the rate gains are apportioned among the cooperating users. We study transmitter and receiver cooperation in an IC as two distinct cooperative models and in each case focus on the stability of the grand coalition (GC) of all users for both flexible (transferable) and fixed (non-transferable) apportioning schemes. We show that the GC is the stable sum-rate optimal coalition when only receivers cooperate by jointly decoding (transferable). However the stability of the GC depends on the detector when receivers cooperate using linear multiuser detectors (non-transferable). For transmitter cooperation it is assumed that all receivers cooperate perfectly and that users outside a coalition act as jammers. We present results on the stability of the GC for both the case of perfectly cooperating transmitters (transferrable) and under a partial decode-and-forward strategy (non-transferable). We show that the stability depends on the channel gains for the former and the transmitter jamming strengths for the latter.BIO: Lalitha Sankar received the B.Tech degree in Engineering Physics from the Indian Institute of Technology, Bombay in 1992, the MS degree in Electrical Engineering from the University of Maryland, Baltimore County in 1994, and the Ph.D degree in Electrical Engineering from Rutgers University in June 2005. She is presently a Science and Technology postdoctoral fellow at Princeton University. After her masters, Lalitha worked for a year at Polaroid Corporation's Engineering R&D, following which she was a Senior Member of Technical Staff at AT&T Shannon Labs until March 2002.Host: Prof. Urbashi Mitra, ubli@usc.edu

Location: Hughes Aircraft Electrical Engineering Center (EEB) - 248

Audiences: Everyone Is Invited

Contact: Mayumi Thrasher