Professor Georgios Giannakis
We are focused on Signal Processing (SP) research and development projects
In Networking (N) and COMmunication (COM) systems. On par with the dramatic
upswing in modern telecommunications and information technology worldwide,
our SPINCOM team contributes enthusiastically its "basic research and
education bits" towards realizing the dream of "communicating with
anyone, anywhere, anytime."
Since 1994, the group has emphasized wireless, mobile telecommunications and
networking research. Current topics include complex-field, space-time and
network coding, multicarrier, cooperative wireless communications, cognitive
radios, cross-layer designs, mobile ad hoc networks, and wireless sensor
networks. Research funding comes from the National Science Foundation (NSF),
the Army Research Office (ARO), the Army's Research Lab (ARL), and the
Office of Naval Research (ONR); we are thankful to all our sponsors for
their support through the years.
Historically, SPINCOM started with the SPIRIT group at the University of
Virginia (1987–1998) that performed research in applications and
algorithms for signal processing, estimation and detection theory,
time-series analysis, and system identification. Specific subjects
included (poly) spectral analysis, wavelets, cyclostationary, and
non-Gaussian signal processing with applications to sonar, array,
and image processing (SAR).
Wireless Cooperative Communications
- Link-Adaptive Relay Protocols
- Multi-Source Cooperation and Network Coding
- Cooperative Synchronization
Ultra-Wideband and Cognitive Radios
- Synchronization and (De-)modulation
- Dynamic Spectrum Management
- Sensing and Scheduling
Cross-Layer Designs
- Adaptive Modulation/Coding with ARQ and Queuing
- Random Access with Decentralized Channel Information
- Scheduling and QoS Support in Wireless Access
Wireless Sensor Networks
- Decentralized Detection and Classification
- Joint Compression-Estimation
- Distributed Consensus-Based Estimation
Wireless Mobile Ad Hoc Networks
- Fundamental Limits and Optimality
- Stochastic Routing Protocols
- Joint Contention and Congestion Control
- Scheduling for Distributed Access
Professor Tian He
My research interests lie broadly in wireless and sensor networking,
distributed systems and real-time computing. Currently, my research is
focusing on Wireless Sensor Networks (WSNs), a new information paradigm
based on the collaboration of a large number of self-organized sensing
nodes. These networks form the basis for many promising applications such
as immersive gaming, intelligent battlefields, hazard response systems,
smart hospitals and cyber-physical systems. My research is mainly
system-oriented - building practical systems. Specifically we are aiming at
four major interleaved efforts: 1) Integrated sensor systems such as
VigilNet , 2) sensor network service such as energy management,
localization, networking, coverage and privacy issues, 3) in-situ empirical
modeling and related protocol enhancement, and 4) architecture, system,
language and development support for large-scale integrated sensor network
systems. The ultimate research goal is to contribute to the design,
implementation, deployment, use and maintenance of practical sensor
systems.
APL - In road networks, sensor nodes are deployed sparsely (hundreds of
meters apart) to save costs. This makes the existing localization solutions
based on the ranging ineffective. To address this issue, we introduce an
Autonomous Passive Localization (APL) scheme. Our work is inspired by the
fact that vehicles move along routes with a known map. Using
vehicle-detection timestamps, we can obtain distance estimates between any
pair of sensors on roadways to construct a virtual graph composed of sensor
identifications (i.e., vertices) and distance estimates (i.e., edges). The
virtual graph is then matched with the topology of road map, in order to
identify where sensors are located in roadways. We evaluate our design in
local roadways and simulated environments, where we found no location
matching error, even with a maximum sensor time synchronization error of
0.3sec and the vehicle speed deviation of 10km/h. This system has been
reported in Infocom 2008.
Mirage is a large indoor sensor network test-bed, supporting up to 360
nodes. The whole test-bed is composed of six 4 feet by 8 feet boards. Each
board in the system can be used as an individual sub-system, because each
board is designed to be separately powered, separately controlled and
separately metered. Each individual board can support up to 60 nodes,
therefore, the whole system can support up to 360 nodes working
simultaneously. In the first phase of construction, three high-end HIT
HITCPX1250 projectors are used to generate event (it is capable to create
mirage ). In the second phase of construction, motorize objects are
introduced to create another sets of mobile targets. The ultimate goal of
this testbed is to allow researchers to conduct all kinds of system research
locally and remotely with realistic sensing modality as inputs. The first
phase of construction is finished during 2007. In the second phase, mobility
support will be added.
VigilNet is one of the major efforts in the sensor network community to
build an integrated sensor network system for surveillance missions. The
focus of this effort is to acquire and verify information about enemy
capabilities and positions of hostile targets. Such missions often involve a
high element of risk for human personnel and require a high degree of
stealthiness. Hence, the ability to deploy unmanned surveillance missions,
by using wireless sensor networks, is of great practical importance for the
military. In this work, we design and implement a complete running system,
called VigilNet, for energy-efficient surveillance. It currently consists
about 40,000 lines of NesC and Java code, running on XSM, Mica2 and Mica2dot
platforms. The complete system is designed to scale to at least 1000 XSM
motes and cover minimal 100x1000 square meters to ensure operational
applicability. We evaluate middleware and system performance extensively on
a network of 203 MICA2 motes.
Professor Zhi-Li Zhang
We conduct research on a broad range of topics related to computer and
communication networks, helping transform the current best-effort Internet
to a more reliable, available and secure information infrastructure for all
kinds of communication activities. Our research spans packet scheduling
disciplines, (Quality of Service) routing, network resource management,
network architecture design, network performance analysis, video streaming,
collaborative systems, and more. In carrying out our research, we blend
formal modeling/analysis, experimentation/implementation, and
testing/evaluation.
