As the number of transistors available on a single chip increases to billions or even larger numbers, multiprocessor systems are becoming attractive choices for high-performance and low-power applications. Traditional on-chip communication architectures for multiprocessor systems face several issues, such as poor scalability, limited bandwidth, and high power consumption. Networks–on-chip (NoCs) relieve multiprocessor systems from these issues by using modern communication and networking theories. Many NoCs have been studied, and most of them are based on metallic interconnects and electronic routers. As new applications continuously push the limits of multiprocessor systems, the conventional metallic interconnects and electronic routers gradually become the bottlenecks of NoC performance due to the limited bandwidth, long delay, large area, high power consumption, and crosstalk noise. Optical interconnects have demonstrated their strengths in multicomputer systems, on-board inter-chip interconnect, and the switching fabrics of Internet routers. Silicon-based optical waveguides can be used to build on-chip optical interconnects. The progress in photonic technologies, especially the development of microresonators, makes optical on-chip routers possible. This talk will present our recent studies on optical NoCs. Optical NoCs use silicon-based optical interconnects and routers, which are compatible with CMOS technologies. They are promising candidates to achieve significant higher bandwidth, lower power, lower interference, and lower delay compared with electronic NoCs.
Dr. Xu is an Assistant Professor of Department of Electronic and Computer Engineering in the Hong Kong University of Science and Technology. He received his Ph.D. degree in Electrical Engineering from Princeton University, USA. He received both the B.S. and M.S. degrees in Electrical Engineering from Harbin Institute of Technology, China. He was a Research Associate of Bell Labs, USA, from 2001 to 2002, and was a Research Associate of NEC Laboratories America from 2003 to 2005. Dr. Xu was a Member of Technical Staff at a startup company in USA from 2005 to 2007. He served on the committee of ICCD, CASES, VLSI, ISVLSI, EMSOFT, etc. His research areas include multiprocessor systems, system-on-chip, computer architecture, low-power VLSI design, and embedded systems.