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Below is a sample of the research projects conducted in the Information Systems
Lab. |
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Message Passing
Faculty: Andrea
Montanari
Message passing algorithms (such as belief propagation) are used in a variety
of applications, ranging from iterative coding to probabilistic inference and
distributed optimization. Our aim is to build theoretical foundations and
guarantees for such algorithms as well as to develop new applications. |
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Convex Optimization
Faculty: Stephen Boyd
We apply modern convex optimization techniques to problems
arising in control, signal processing, networks, and circuit
design. Recent applications include statistical design of circuits and
fast converging distributed systems.
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Network Information Theory
Faculty: Tom Cover, Abbas El Gamal
Research in network information theory is motivated by the increasing
interest in ad hoc and wireless sensor networks. Our current projects
apply tools from information theory and networking to establish limits
on the performance for wireless networks.
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Imaging System Architectures
Faculty: Abbas El Gamal
Research in imaging architectures is motivated by recent developments
in submicron CMOS image sensor technologies and the emergence of 3D
integration. Our current projects aim to exploit these technologies to
develop high dynamic range and high speed imaging systems for
industrial and tactical applications, ultra high sensitivity
lab-on-chips for biological testing applications, and algorithms for
collaborative computing over imaging sensor networks. |
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Image, Video, and
Multimedia Systems
Faculty: Bernd Girod
We conduct fundamental and
applied research on various aspects of video compression, coding, and
networked real-time media systems. Current topics include wavelet
video coding, distributed video coding, light field compression and
streaming, rate-distortion optimized packet scheduling, and video
streaming over ad hoc wireless networks.
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Wireless Systems
Faculty: Andrea Goldsmith
Our research is focused on wireless system design for multimedia
communications, sensor networks, and distributed control. We explore
the fundamental capacity limits of these systems as well as practical
designs. Specific research areas include capacity of wireless
channels and networks, adaptive resource allocation, multiantenna
wireless systems, energy and delay constrained wireless networks, and
cross-layer design for cellular systems, ad-hoc wireless networks,
and sensor networks.
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Wireless Sensor Networks
Faculty: Andrea Goldsmith
Wireless sensor network design is a multi-disciplinary area with many
challenging open problems in both theory and system design. Our
research in this area focuses on ad-hoc wireless network design,
communication under severe energy constraints, collaborative
communication, cross-layer design, distributed control and signal
processing, and data aggregation and fusion.
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Compression and Classification
Faculty: Robert Gray, Richard Olshen
We work on a mix of statistical signal processing, statistical
classification, and data compression topics. Our particular interests are in
high rate quantization theory, Shannon rate-distortion theory, and
applications of quantization-based statistical clustering algorithms to
image coding and classification. Recent work has emphasized clustering
of Gauss mixture models and anonomoly detection in North Atlantic gas
pipeline images.
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Incentives in Engineered Systems
Faculty: Ramesh Johari
We study the interplay between engineered systems and economic
incentives. Key areas of research include: the impact of communication
and computation constraints on achievable game theoretic performance;
competition and cooperation among Internet service providers; and
design and analysis of power market architectures.
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Magnetic Resonance Systems
Faculty: Dwight Nishimura, Al Macovski, John Pauly
The Magnetic Resonance Systems Research Lab develops new acquisition
and processing methods for improved magnetic resonance imaging. The
lab operates a whole-body 1.5 T scanner for its experiments. Projects
include new approaches to MRI using two magnets, noninvasive blood
vessel imaging, and real-time MRI with reduced artifacts.
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Smart Antennas
Faculty: Arogyaswami Paulraj
We seek to improve the spectrum efficiency/capacity, link reliability
and coverage of wireless networks. Space-time wireless technology uses
multiple antennas with appropriate signaling and receiver techniques
offering a powerful tool for improving wireless performance.
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Image Guided Interventions
Faculty: John Pauly
Magnetic resonance imaging (MRI) has superb soft tissue contrast
without requiring ionizing radiation. These features could make MRI
an ideal imaging modality for guiding therapeutic interventions. This
project addresses the significant technical problems that must first
be solved. These include real-time visualization and tracking of
passive and active devices, real-time monitoring of therapy, and
design and fabrication of active intravascular devices.
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Network Algorithms
Faculty: Balaji Prabhakar
Internet traffic follows "power law distributions;" an important
implication is that 80% percent of packets are generated by 10% of the
flows. Serious advantage could be taken of such a statistic *if* we
could identify the packets of these large flows with minimal overhead.
We have recently developed a simple randomized algorithm, called SIFT,
for doing just this. We are
currently exploring the application of SIFT to simplify buffer
management, address lookup and switch scheduling algorithms in core
Internet routers.
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Statistical Physics meets Optimization and Algorithms
Faculty: Balaji Prabhakar, Andrea Montanari
Major questions in statistical physics are: What is the degree of
magnetization at a certain temperature? What is the corresponding
"free energy?" Physicists have advanced a remarkable heuristic called
the Replica Method to get *explicit* answers to some of these
questions. A fundamental truism links optimization to statistical
physics: Nature optimizes. So it is natural to apply the
Replica Method to combinatorial optimization problems (satisfiability,
turbo-decoding, minimum weight matching, etc) even though these don't
arise in the physical world.
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Wireless Networks
Faculty: Balaji Prabhakar, Abbas El Gamal, Stephen Boyd
These networks are being developed for indoor surveillance, emergency
infrastructureless communication, and inter-automobile communication.
We have been working on three distinct theoretical problems:
energy-efficient transmission, an
analysis of the trade-off between throughput and delay, and developing
and analyzing algorithms for data aggregation and information
exchange. In collaboration with Bosch Research we have also developed
some practical algorithms for deployment in commercial surveillance
networks.
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Dynamic Optimization
Faculty: Benjamin Van Roy
We develop algorithms that optimize decision strategies for situations in
which a sequence of decisions is required as a system evolves and
uncertainty unfolds. This work is relevant to many application areas,
and recently, we have been interested in dynamic pricing, queueing
network scheduling, and trading.
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Delay-Constrained and Complexity-Constrained Information Theory
Faculty: Tsachy Weissman
Source and channel coding systems can be classified according to
various restrictions on their operations, including causality,
delay constraints, memory constraints, and the availability of side
information. We study the optimum performance attainable under various
combinations of such restrictions. We also apply our theoretical
findings to develop practical real-time coding schemes.
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Denoising and Filtering
Faculty: Tsachy Weissman
We investigate both theoretical and applied aspects of noise removal
from corrupted signals and corrupted data sets. The scope of the work
ranges from establishing fundamental performance limits, through
studying universality and algorithmic aspects, to experimentation with
simulated and real data.
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Learning Systems, Adaptive Filters and Neural Networks
Faculty: Bernard Widrow
We research signal processing systems, control systems, pattern
recognition systems, etc., that self adjust and learn from
experience. Both theory and practical application are emphasized. Major
applications have been in the communications, control, and biomedical
areas. We are currently developing a "cognitive memory", a computer
memory patterned after human memory.
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