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Events for January 28, 2011
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Polarization Attributes of Stimulated Brillouin Scattering in Fibers
Fri, Jan 28, 2011 @ 10:00 AM - 11:00 AM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
Speaker: Dr. Avi Zadok, Bar-Ilan University
Talk Title: Polarization Attributes of Stimulated Brillouin Scattering in Fibers
Abstract: Stimulated Brillouin scattering (SBS) is a nonlinear optical interaction between a pump wave, and a typically weaker, counter-propagating signal wave. The threshold power of SBS is the lowest of all nonlinear propagation effect in silica optical fibers. The local SBS interaction, at a given point along an optical fiber, is maximal when the state of polarization (SOP) of the pump is aligned with that of the signal, and it vanishes if the two SOPs are orthogonal. In standard single mode fibers, the overall SBS signal amplification (or attenuation) depends on the birefringence properties of the fiber, as well as on the input SOPs of both the pump and the seed signal waves. As SBS is studied intensively for applications such as fiber lasers, distributed sensing and slow light, a thorough examination of its polarization properties is of large relevance.
In this talk, the SBS amplification of an arbitrarily polarized input signal in a randomly birefringent fiber is examined, as well as the role of SBS in the evolution of the signal SOP. The analysis includes Stokes and anti-Stokes waves. A propagation equation for the signal SOP is formulated and analyzed, in Jones and Stokes spaces. In particular, it is found that the output SOP of an SBS amplified Stokes wave in a standard, single mode fiber is drawn towards the complex conjugate of the input pump SOP. On the other hand, the output SOP of the residual, attenuated anti-Stokes signal is repelled from the same SOP. These findings are supported by simulations and experiments. The results are applicable to random SOP synthesis, coherent detection of fiber sensors, advanced modulation formats and implementations of optical filters. Finally, the role of polarization in SBS-based 'slow light' setups is addressed.
Biography: Avi Zadok received his Ph.D. in Electrical Engineering from Tel-Aviv University in 2007. In between 2007-2009 he was a post-doc fellow with the group of Prof. Amnon Yariv at the Department of Applied Physics, California Institute of Technology. In 2009 he was appointed as a senior lecturer at the School of Engineering, Bar-Ilan University. His research interests include silicon-photonic devices, fiber-optic communication and sensors, microwave photonics and nonlinear optics.
Host: Prof. Alan Willner, willner@usc.edu
Location: Hughes Aircraft Electrical Engineering Center (EEB) - 349
Audiences: Everyone Is Invited
Contact: Gerrielyn Ramos
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Viterbi Ball Ticket Sales
Fri, Jan 28, 2011 @ 11:00 AM - 02:00 PM
Viterbi School of Engineering Student Organizations
Student Activity
Come buy your tickets for Viterbi Ball! $25 each, checks made out to USC or cash accepted.
Visit the Facebook event for more info: http://www.facebook.com/event.php?eid=170374009672457
Location: E-Quad
Audiences: Undergrad
Contact: VSC
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Integrated Systems Seminar Series
Fri, Jan 28, 2011 @ 12:00 PM - 01:00 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
Speaker: Dr. Kris Merkel, President/CEO of S2 Corporation
Talk Title: Sustainable Ultra-Wideband Radio Frequency Signal Analysis Using Spatial-Spectral Holography
Abstract: I will cover the basics of the interaction of coherent light with cryogenically cooled rare earth doped crystal absorbers, and how this science has evolved as a basis for an emerging technology known as spatial-spectral (S2) holography. I will also comment on performing R&D in a commercial small business setting that has been funded primarily by the Small Business Innovative Research (SBIR) program.
The core S2 technology has its roots in the coherent interaction of light with matter, and can combines frequency resolution with angular phase resolution similar to spatial holography. Signal processing functions of spectral analysis, direction finding, correlative signal processing and true time delay will be discussed. The general technical approach to an ultra wideband RF receiver is based on recording and subsequent readout of optical energy that is modulated to represents RF frequencies via conversion by an electro-optical phase modulator (EOPM). The modulated light is absorbed by the holographic crystal. The S2 sensor performs physical phase sensitive Fourier transforms and multiplication of Fourier transforms. These transforms are stored in atomic upper states, and then can be probed or readout by a secondary light source.
A current hardware configuration can support 100% time-continuous coverage for 20 GHz instantaneous bandwidth (IBW) measurements with ~400 kHz resolution bandwidth (RBW), and a full 20 GHz bandwidth readout every 0.5 ms. A spur free dynamic range of 50 dB is observed for these measurements. Other approaches can provide variations on these specifications.
Biography: Dr. Kris Merkel is the President/CEO of S2 Corporation. Dr. Merkel has focused his 15 years of experience on the development and application of S2 technology relative to radar, laser radar, electronic surveillance and true time delay beam-forming systems. Dr. Merkel has overseen the successful execution of several contracts and grant with milestones met within cost. He received his Bachelor of Physics from Georgetown University (1994) and his Masters (1996) and Ph.D (1998) in Electrical Engineering from the University of Washington. Dr. Merkel is a recognized world leader in the development of S2 systems, and is an inventor on 10 patents and patents pending. Dr. Merkel has unique capabilities related to a combination of project management and technical expertise for systems development efforts. He has over 25 publications in referred journals and conference proceedings.
Host: Prof. Hossein Hashemi and Firooz Aflatouni
Location: Hughes Aircraft Electrical Engineering Center (EEB) - 248
Audiences: Everyone Is Invited
Contact: Hossein Hashemi
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W.V.T. Rusch Engineering Honors Colloquium; Living with Complex Technological Systems: Lessons from Bopal to BP Deep Water Horizon
Fri, Jan 28, 2011 @ 01:00 PM - 01:50 PM
USC Viterbi School of Engineering
Conferences, Lectures, & Seminars
Speaker: Prof. Najmedin Meshkati, Sonny Astani Dept. of Civil and Environmental Engineering
Talk Title: W.V.T. Rusch Engineering Honors Colloquium; Living with Complex Technological Systems: Lessons from Bopal to BP Deep Water Horizon
Abstract: Prof. Najmedin Meshkati, Sonny Astani Department of Civil and Environmental Engineering at the University of Southern California, will present "Living with Complex Technological Systems: Lessons from Bopal to BP Deep Water Horizon" as part of the W.V.T. Rusch Engineering Honors Program.
Host: W.V.T. Rusch Engineering Honors Colloquium
More Info: http://viterbi.usc.edu/students/undergrad/honors/schedules/Location: Seeley G. Mudd Building (SGM) - 101
Audiences: Undergrad
Contact: Amanda Atkinson
Event Link: http://viterbi.usc.edu/students/undergrad/honors/schedules/
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Making Run-time Reconfigurable Hardware more Useful
Fri, Jan 28, 2011 @ 03:00 PM - 04:00 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
Speaker: Jim Torresen, University of Oslo
Talk Title: Making Run-time Reconfigurable Hardware more Useful
Abstract: Before the introduction of multitasking operating systems around 1985, processors would run one program at a time. The program would be uploaded at startup and run until finished. There would be no swapping to other programs during execution of a given program. With todayâs multitasking operating systems, it would often be the exception not performing multitasking for software. This is in contrast to hardware which normally is static at run-time even though reconfigurable hardware is programmable at run-time.
This talk will introduce and describe how we are applying FPGA (Field Programmable Gate Arrays) technology for designing high performance run-time reconfigurable computing architectures. This is research undertaken through the project named Context Switching Reconfigurable Hardware forCommunication Systems (COSRECOS), funded by the Research Council of Norway for 2009 â 2013.
The overall goal of the project is to contribute in making run-time reconfigurable systems more feasible in general. This includes introducing architectures for reducing reconfiguration time as well as undertaking tool development. Case studies by applications in network and communication systems will be a part of the project. The talk includes how we plan to address the challenge of changing hardware configurations while a system is in operation as well as giving an overview of promising initial results so far.
Biography: Jim Torresen received his M.Sc. and Dr.ing. (Ph.D) degree in computer architecture and design from the Norwegian University of Science and Technology, University of Trondheim in 1991 and 1996, respectively. He has been employed as a senior hardware designer at NERA Telecommunications (1996-1998) and at Navia Aviation (1998-1999).
Since 1999, he has been a professor at the Department of Informatics at the University of Oslo (associate professor 1999-2005). Jim Torresen has been a visiting researcher at Kyoto University, Japan for one year (1993-1994), four months at Electrotechnical laboratory, Tsukuba, Japan (1997 and 2000) and is now a visiting professor at Cornell University.
His research interests at the moment include bio-inspired computing, machine learning, reconfigurable hardware, robotics and applying this to complex real-world applications. Several novel methods have been proposed. He has published a number of scientific papers in international journals, books and conference proceedings. 10 tutorials and several invited
talks have been given at international conferences. He is in the program committee of more than ten different international conferences as well as a regular reviewer of a number of international journals. He has also acted as an evaluator for proposals in EU FP7.
Host: Professor Viktor K. Prasanna
Location: Hughes Aircraft Electrical Engineering Center (EEB) - 248
Audiences: Everyone Is Invited
Contact: Janice Thompson
