Research Challenges in Low-Duty-Cycle Wireless Networks

Monday, October 12, 2009

Abstract

Wireless networks have been widely adopted for Internet accesses, location-aware service, peer-to-peer data sharing and remote wireless sensing. For decades, many researchers have been focusing on wireless networks in which devices are assumed to be ready to receive incoming packets, ignoring the fact that idle listening dominates energy consumption, especially in emerging low-rate low-power wireless transceivers (e.g., 802.15.4). To reduce the energy costs of idle listening, a device has to reduce its duty-cycle by sampling RF channels very briefly and shutting down for long periods. At any given time, this type of network is actually fragmented and network connectivity becomes intermittent, wherein a sender suffers sleep latency, i.e., a delay waiting for an intended receiver to wake up. With the increasing gap between the long lifetime requirements and slow progress in battery technology, low-duty-cycle networking is a crucial future foundation for many energy-constrained wireless applications (e.g., low-power sensing, actuation, tagging and alert). However, the little research that has been done in this area predominately focuses on individual physical designs and the need for network level research becomes increasing important. This talk introduces the latest development in low-duty-cycle networking research with the focus on how to optimize networking performance (e.g., delay, reliability, and cost) in the presence of sleep latency, unreliable links and dynamic energy availability.

Bio

Dr. Tian He is currently an assistant professor in the Department of Computer Science and Engineering at the University of Minnesota-Twin City. He received the Ph.D. degree under Professor John A. Stankovic from the University of Virginia, Virginia in 2004. Dr. He is the author and co-author of over 90 papers in premier sensor network journals and conferences with over 4000 citations. His publications have been selected as graduate-level course materials by over 50 universities in the United States and other countries. Dr. He has received a number of research awards in the area of sensor networking, including four best paper awards (MSN 2006 and SASN 2006, MASS 2008, MDM 2009). Dr. He is also the recipient of the NSF CAREER Award 2009 and McKnight Land-Grant Professorship 2009-2011. Dr. He served a few program chair positions in international conferences and on many program committees, and also currently serves as an editorial board member for four international journals including ACM Transactions on Sensor Networks. His research includes wireless sensor networks, intelligent transportation systems, real-time embedded systems and distributed systems, supported by National Science Foundation and other agencies. Dr. He is a member of ACM and IEEE.