Abstract: Relay is a natural way of extending communication range, which has been employed by human societies with a long history. In modern times, relay became a basic component in various technological developments. Although the basic principle of relay is simple, its optimal operation is generally not easy to establish. Specially, in wireless communications, there have been tremendous efforts in determining the optimal relay strategies, which still remain elusive after the problem has been openly posted for more than thirty years. However, recent years have seen steady progresses on this topic and its generalizations. In this talk, I will reflect on these achievements and their significance for applications. Rather than the mathematics, my talk will be focusing on the ideas that were key to these developments. 

Bio:Liang-liang Xie is a professor of Department of Electrical and Computer Engineering University of Waterloo. He received the B.S. degree in mathematics from Shandong University and the Ph.D. degree in ontrol theory from the Chinese Academy of Sciences in 1995 and 1999, respectively. He did postdoctoral research at the Automatic Control Group , Linköping University, Sweden during 1999-2000 and at the Coordinated Science Laboratory, University of Illinois at Urbana-Champaign, USA during 2000-2002.