Presented by: Dr. Shuvra S. Bhattacharyya

Date: Friday, May 24, 2013
Time: 11:00 am - 12:00 pm
Place: ECS 660

Abstract:

With the increasing need for accurate mining and classification from multimedia data content, and the growth of such multimedia applications in mobile and distributed architectures, stream mining systems require increasing amounts of flexibility, extensibility, and adaptivity for effective deployment. In this talk, I will present a novel approach to address this challenge. This approach rigorously integrates foundations of dataflow modeling for high level signal processing system design, and adaptive stream mining based on dynamic topologies of classifiers. In particular, I will introduce a new design environment, called the lightweight dataflow for dynamic data driven adaptive systems (LiD4E) environment. LiD4E provides formal semantics, rooted in dataflow principles, for design and implementation of a broad class of multimedia stream mining topologies. I will demonstrate the capabilities of LiD4E using a face detection application that systematically adapts the type of classifier used based on dynamically changing application constraints.

This work being carried out jointly with Kishan Sudusinghe, Stephen Won, and Mihaela van der Schaar.

Biographical sketch:

Shuvra S. Bhattacharyya is a Professor in the Department of Electrical and Computer Engineering at the University of Maryland, College Park. He holds a joint appointment in the University of Maryland Institute for Advanced Computer Studies (UMIACS). He is coauthor or coeditor of six books, and the author or coauthor of over 220 papers in the areas of signal processing, embedded systems, electronic design automation, wireless communication, and wireless sensor networks. His research interests include signal processing systems and architectures; wireless sensor networks; embedded software; and hardware/software co-design. He received the B.S. degree from the University of Wisconsin at Madison, and the Ph.D. degree from the University of California at Berkeley. He has held industrial positions as a Researcher at the Hitachi America Semiconductor Research Laboratory (San Jose, California), and Compiler Developer at Kuck & Associates. (Champaign, Illinois).  He has held a visiting research position at the US Air Force Research Laboratory (Rome, New York). He is a Fellow of the IEEE.

For further information, contact:
Mihai Sima (250-721-8680 msima@ece.uvic.ca)

Presented by: Dr. Mohamed-Slim Alouini - Professor, Division of Physical Sciences and Engineering, King Abdullah University of Sciences and Technology (KAUST)

Date: Monday, May 27, 2013
Time: 1:30 pm - 2:30 pm
Place: EOW 430

Abstract:

Exact and asymptotic studies of the average error probability of wireless communication systems over generalized fading channels have been extensively pursued over the last two decades. In contrast, studies and results dealing with the channel capacity in these environments have been more scarce. In the first part of this talk, we present a generic moment generating function-based approach for the exact computation of the channel capacity in such kind of environments. The resulting formulas are applicable to systems having channel state information (CSI) at the receiver and employing maximal-ratio combining or equal-gain combining multichannel reception. The analysis covers the case where the combined paths are not necessarily independent or identically distributed. In all cases, the proposed approach leads to an expression of the ergodic capacity involving a single finite-range integral, which can be easily computed numerically. In the second part of the talk, we focus on the asymptotic analysis of the capacity in the high and low signal-to-noise ratio (SNR) regimes. More specifically, we offer new simple closed-form formulas that give an intuitive understanding of the capacity behavior at these two extreme regimes. Our characterization covers not only the case where the CSI is available only at the receiver but also the case where the CSI is available at both the transmitter and receiver.

Biography:

Mohamed-Slim Alouini received his Ph.D. degree in Electrical Engineering from the California Institute of Technology (Caltech), Pasadena, CA, USA, in 1998. He was with the department of Electrical and Computer Engineering of the University of Minnesota, Minneapolis, MN, USA, then with the Electrical and Computer Engineering Program at the Texas A&M University at Qatar, Education City, Doha, Qatar. Since June 2009, he has been a Professor of Electrical Engineering in the Division of Physical Sciences and Engineering at King Abdullah University of Sciences and Technology (KAUST) Thuwal, Makkah Province, Kingdom of Saudi Arabia, where his current research interests include the design and performance analysis of wireless communication systems.

For further information, contact:
Xiaodai Dong (250-721-6029, xdong@ece.uvic.ca)

Presented by: Dr. Rui Zhang - Assistant Professor, Department of Electrical and Computer Engineering, National University of Singapore

Date: Monday, May 27, 2013
Time: 2:30 pm - 3:15 pm
Place: EOW 430

Abstract:

Energy-constrained wireless networks such as sensor networks are typically powered by batteries that have limited operation time. Although replacing or recharging the batteries can prolong the lifetime of the network to a certain extent, it incurs high costs and is inconvenient, hazardous (say, in toxic environments), or even impossible (e.g., for sensors embedded in building structures or inside human bodies). A more economic, convenient, safer, as well as greener alternative solution is thus to harvest energy from the environment, which virtually provides perpetual energy supplies to wireless devices. In addition to other commonly used energy sources such as solar and wind, ambient radio-frequency (RF) signals can be a viable new source for energy scavenging. Since RF signals can be utilized for information transmission at the same time, a unified study on simultaneous wireless information and power transfer (SWIPT) has recently drawn growing attention. In this talk, we will first provide a brief survey on the history of wireless power transfer and its state-of-the-art applications and enabling technologies including magnetic induction, magnetic resonance, and EM radiation. Next, we will focus on the RF signal (EM radiation) enabled wireless power transfer, and introduce several new challenges in designing wireless powered communication networks. We will characterize the fundamental rate-energy tradeoffs in SWIPT systems and present some novel solutions to practically achieve/approach such fundamental limits.

Biography:

Rui Zhang received the B.Eng. (First-Class Hons.) and M.Eng. degrees from the National University of Singapore in 2000 and 2001, respectively, and the Ph.D. degree from the Stanford University, Stanford, CA USA, in 2007, all in electrical engineering. Since 2007, he has worked with the Institute for Infocomm Research, A*STAR, Singapore, where he is now a Senior Scientist. Since 2010, he has joined the Department of Electrical and Computer Engineering at the National University of Singapore as an Assistant Professor. He has authored/coauthored over 140 internationally refereed journal and conference papers in the field of wireless communications. His current research interests include multiuser MIMO, cognitive radio, cooperative communication, green communication, wireless networks powered by energy harvesting and wireless power transfer, smart grid, and optimization theory. Dr. Zhang was the co-recipient of the Best Paper Award from the IEEE PIMRC in 2005. He was the recipient of the 6th IEEE ComSoc Asia-Pacific Best Young Researcher Award in 2010, and the Young Investigator Award of the National University of Singapore in 2011. He is now an elected member of IEEE Signal Processing Society SPCOM & SAM Technical Committees, and an editor for the IEEE Transactions on Wireless Communications.

Light refreshments will be served.

For further information, contact:
Xiaodai Dong (250-721-6029 xdong@ece.uvic.ca)

Presented by: Dr. Wei Zhang - Associate Professor, School of EET, The University of New South Wales, Sydney, Australia, Visiting Associate Professor, Dept. of ECE, Hong Kong University of Science & Technology

Date: Monday, May 27, 2013
Time: 3:15 pm - 4:00 pm
Place: EOW 430

Abstract:

Interference alignment has been recently studied as an effective tool to achieve degree of freedom (DoF) of wireless interference channels. DoF is also known as multiplexing gain or capacity pre-log scaling factor and provides a capacity approximation of wireless network in the high signal-to-noise ratio region. However, the interference alignment technique requires precoder design with the channel state information at transmitters (CSIT) so that the interferences can be aligned at receivers. Blind interference alignment can overcome the limitation of full CSIT by adopting pattern reconfigurable antennas at receivers. In this talk, the wireless interference channel is investigated from a different perspective and the diversity benefits of wireless interference channels are explored. A space-time coding approach is designed to achieve high diversity gain and high rate for MISO interference channels with reconfigurable receiver antennas. A family of space-time codes is proposed with blind interference alignment to accommodate various needs of diversity-rate tradeoff.

Biography:

Wei Zhang received the PhD degree in EE from the Chinese University of Hong Kong in 2005. He was Research Fellow at the Department of Electronic and Computer Engineering, Hong Kong University of Science and Technology (HKUST) in 2006-2007. In 2008, he joined the School of Electrical Engineering and Telecommunications, The University of New South Wales, Sydney, Australia, where he is currently Associate Professor. Also, he is now on sabbatical leave at HKUST as Visiting Associate Professor. His current research interests include cognitive radio, cooperative communications, space-time coding, and multiuser information theory. He received the best paper award at the 50th IEEE Global Communications Conference (GLOBECOM), Washington DC in 2007 and the IEEE Communications Society Asia-Pacific Outstanding Young Researcher Award in 2009. He is an Editor of IEEE Transactions on Wireless Communications and an Editor of IEEE Journal on Selected Areas in Communications (Cognitive Radio Series). He served as a TPC Co-Chair of Communications Theory Symposium of IEEE ICC 2011. Currently, he serves a TPC Co-Chair of Wireless Communications Symposium of IEEE ICCC 2013.

Email: w.zhang@unsw.edu.au Web: http://www2.ee.unsw.edu.au/~wzhang/

Light refreshments will be served.

For further information, contact:
Xiaodai Dong (250-721-6029 xdong@ece.uvic.ca)