Talk given at AIT by Professor Urbashi Mitra, Ming Hsieh Department of Electrical Engineering, University of Southern California
31 March 2017
You are all invited to the following talk to be given by Professor Urbashi Mitra, Ming Hsieh Department of Electrical Engineering, University of Southern California .
will visit AIT on Tuesday April 6 and will give a presentation entitled:
"Cross-layer estimation and control for Cognitive Radio: Exploiting Sparse Network Dynamics"
The talk will start at 12:00.
Cognitive radio was introduced in the late 1990s as a concept to improve efficiency of spectrum use. Opportunistic users would sense spectral holes and exploit unused spectrum.
The original strategy suggested that spectrum being employed by primary, legacy users should be strictly avoided in order to ensure no interference to the primary users. However, this strict ``white space’’ approach is also inherently spectrally inefficient. In this talk, we review several strategies that limit interference to primary users while significantly improving the throughput of secondary, opportunistic users. The basic idea of the new approach is to exploit the fact that, typically the primary channel is not fully loaded by the primary user service, thus leaving a non-negligible margin to accommodate the cognitive transmission.
Furthermore, the exploitation of such a load margin can be optimized in a variety of ways including shaping the spectrum of the secondary user, optimizing retransmission protocols and jointly designing methods by which to do dynamic spectrum sensing and allocation via cross-layer approaches. Sensing and access are jointly controlled to maximize the secondary user throughput.
The sparsity of the spectrum dynamics is exploited: leveraging a prior spectrum occupancy estimate, the central controller needs to estimate only a residual uncertainty vector via sparse recovery techniques. Sparse recovery methods tailored to the Markov Decision Process modeling of the system are provided and shown to offer strong performance improvement over prior approaches. Our framework yields sensing-scheduling schemes that are most informative for network control, yielding energy efficient resource utilization. The new methods are summarized and performance gains are highlighted.
Urbashi Mitra received the B.S. and the M.S. degrees from the University of California at Berkeley and her Ph.D. from Princeton University. She has been a Member of Technical Staff at Bellcore and faculty at the Ohio State University (OSU). Dr. Mitra is currently a Dean’s Professor of Electrical Engineering at the University of Southern California (USC), Los Angeles. She is the inaugural Editor-in-Chief for the IEEE Transactions on Molecular, Biological and Multi-scale Communications. She is a member of the IEEE Information Theory Society's Board of Governors (2002-2007, 2012-2017), the IEEE Signal Processing Society’s Technical Committee on Signal Processing for Communications and Networks (2012-2016), the IEEE Signal Processing Society’s Awards Board (2017), and the Vice Chair of the IEEE Communications Society, Communication Theory Working Group (2017). She is the recipient of: a 2015 UK Royal Academy of Engineering Distinguished Visiting Professorship, a 2015 US Fulbright Scholar Award, a 2015-2016 UK Leverhulme Trust Visiting Professorship, IEEE Communications Society Distinguished Lecturer, 2012 Globecom Signal Processing for Communications Symposium Best Paper Award, 2012 US National Academy of Engineering Lillian Gilbreth Lectureship, the 2009 DCOSS Applications & Systems Best Paper Award, IEEE Fellow, Texas Instruments Visiting Professor (Fall 2002, Rice University), 2001 Okawa Foundation Award, 2000 OSU College of Engineering Lumley Award for Research, 1997 OSU College of Engineering MacQuigg Award for Teaching, and a 1996 National Science Foundation CAREER Award. She has been an Associate Editor for the following IEEE publications: Transactions on Signal Processing, Transactions on Information Theory, Journal of Oceanic Engineering, and Transactions on Communications. She has co-chaired: (technical program) 2018 SPAWC, Kalamata Greece, technical area chair for Communications at the 2017 Asilomar Conference on Signals, Systems, and Computers, 2014 IEEE International Symposium on Information Theory in Honolulu, HI, 2014 IEEE Information Theory Workshop in Hobart, Tasmania, IEEE 2012 International Conference on Signal Processing and Communications, Bangalore India, and the IEEE Communication Theory Symposium at ICC 2003 in Anchorage, AK; and general co-chair for the first ACM Workshop on Underwater Networks at Mobicom 2006, Los Angeles, CA. Dr. Mitra has held visiting appointments at: King’s College, London, Imperial College, the Delft University of Technology, Stanford University, Rice University, and the Eurecom Institute. Her research interests are in: wireless communications, communication and sensor networks, biological communication systems, detection and estimation and the interface of communication, sensing and control.
"I started my research for suitable educational establishments encompassing all the above elements, as well as being flexible to working individuals and being at home, and AIT came up as the number one choice. In particular the MBIT Master program of AIT looked very appealing to me at the time. Two years later and having compared the investment made (time, effort, cost) to the returns, well, I can tell you the returns are much higher than your expectations!"
Theo Bassayiannis, MBIT 2006 (Greece)