DATE: Thursday, April 15, 2010
TIME: 12:00 pm - 1:00 pm
PLACE: Gates Center 8102

Lin Zhong, Rice University

TITLE: From Users to Energy-efficient Mobile Internet

Recent years have seen an explosive growth of Internet-ready mobile devices such as smartphones, netbooks, and e-Book readers. Not only has the growth challenged the network capacity, but also Internet access is among the most power-hungry usage on mobile devices.

In this talk, we examine the fundamental inefficiency in the design of mobile wireless systems and its impact on both network capacity and device efficiency. In particular, we show the conventional assumption of omni directional transmission from mobile devices is a bottleneck and focus on our recent results in realizing directional transmission for them. We first analyze how mobile devices rotate during real wireless usage and how rotation impacts the quality of directional transmission. Leveraging these findings, we provide two realizations of directional transmission based on directional antennas and energy-efficient beamsteering that are intended for immediate and long-term deployments, respectively. Using both experimental measurement and simulation, we show that directional transmission offers improved capacity-efficiency tradeoffs for mobile Internet access.

Throughout this talk, we emphasize a user-centered approach toward energy-efficient mobile system design to reveal design problems, discover new opportunities, and evaluate solutions.

Lin Zhong received his B.S. and M.S. from Tsinghua University in 1998 and 2000, respectively. He received his Ph.D. from Princeton University in September, 2005. He worked with NEC Labs, America, for the summer of 2003 and with Microsoft Research for the summers of 2004 and 2005. Since September, 2005, he has been with the Department of Electrical & Computer Engineering, Rice University, as an assistant professor. He received the AT&T Asian-Pacific Leadership Award in 2001 and the Harold W. Dodds Princeton University Honorific Fellowship for 2004-2005. He and his students received the best paper awards from ACM MobileHCI 2007 and IEEE PerCom 2009. A paper he co-authored was identified as one of the 30 most influential papers in the first 10 years of Design, Automation & Test in Europe conferences by the conference. His research interests include mobile & embedded system design, human-computer interaction, and nanoelectronics. His research has been funded by National Science Foundation, Motorola Labs, Microsoft Research, Nokia, and Texas Instruments.

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