LINK LAB
People
Prof. Heather Zheng
Lili Cao (PhD)
Ashwin Sampath (PhD)
Lei Yang (PhD)
In the News
Cognitive radio is one of the 2006 MIT
TR 10
emerging technologies. Prof. Zheng was featured in the
article.
A recent presentation Prof. Zheng gave at Dyspan
2005
general session on rule
based
spectrum management, followed by a panel discussion on the
paper.
The paper can be found here.
Prof. Heather Zheng selected as TR35: 2005
MIT Technology Review Top 35 Innovators under the
age of 35 (UCSB
& UMCP
news)
Prof. Zheng's talk at UC Berkeley Networking Seminar on Managing Open Spectrum Systems ,
Oct. 10,
05; also at Bell-Labs, NJ, Sept. 05.
CS290F in Winter
2006 on
intelligent
wireless systems; will continue on Winter 2007.
Links
FAQ for prospective
students
For LINK lab
members
Prof. Ben
Zhao &
UCSB Current Lab
Conferences
Dyspan07 11/15
Contact
Prof. Haitao (Heather) Zheng
Engineering I, 1121
Computer Science, UCSB
Santa Barbara, California 93106-5110
Phone: +1 (805) 893-3560
Fax: +1 (805) 893-8553 
QualNet Network Simulator
Intelligent Networking
The fundamental concept behind Intelligent Networking is to push Human
brain-power into end-devices. Human are intelligent and adaptive. We
sense neighborhood environment, adapt to dynamics and variations, and
learn from past experiences to change future behavior. This is so
called cognitive cycle.
Our approach is to apply the concept of cognitive to network elements
that allows networks to manage themselves in a self-aware and adapative
manner. Areas to be addressed include
self-organizing networks, adaptive routing and MAC protocol design,
network resource
management, topology discovery/control, security as well as network
infrastructures.
- Application of reasoning and learning to facilitate improved efficiency, performance, fault-tolerance, security and other funcationality of networks.
- Introduction of adaptive self-organization to provide fault-tolerant, reliable operations in resource constrained networks.
- Introduction of device collaboration to optimize network operation in a distributed way.
- Exploiting cognitive radio enabled open spectrum systems
to
enhance connectivity, improve capacity and reduce cost.
Current Projects - Routing and MAC
- Managing Open Spectrum Systems
- Reconfigurable Testbed
- Security and Defense
Past Projects
A
Short Introduction
to Cognitive Radio and Open Spectrum
Wireless devices are becoming ubiquitous, placing
increasing stress on the fixed radio spectrum available to all access
technologies. This
leads to spectrum scarcity problem. To eliminate interference between
different wireless technologies,
traditional (and current) policies allocate a fixed spectrum slice to
each technology, i.e.
command
and
control. This static assignment prevents devices from efficiently
utilizing allocated spectrum, resulting in spectrum holes (no targeted
devices in local area) and very poor utilization (6-10%) in other
geographic
areas (source DARPA). Given that the current spectrum licensing policy
facing near-future threat of spectrum scarcity and the increasing crowd
in unlicensed spectrum band, efficient spectrum management is necessary
and critical to future development of system and networking.
Enabled by software defined radio (SDR)
technology, Open Spectrum allows unlicensed (secondary) users to share
spectrum with legacy (primary)
spectrum users, thereby "creating" new capacity and commercial
value from existing spectrum ranges. Based on agreements and
constraints
imposed by primary users, secondary users opportunistically utilize
unused
licensed spectrum on a non-interfering or leasing basis. Open Spectrum
systems have a high potential for impact, and can enable large segments
of the world population to be connected efficiently and cost
effectively using a variety of devices, while making world-wide
deployment easy for service providers. It is envisioned to have an
impact on wireless system and networking like the way that Internet and
packet switching have reshaped the world.
Open spectrum requires a new line of
cognitive radios. Cognitive refers to a device's ability to sense
surrounding environment conditions and adapt its behavior accordingly.
This process is often referred to as cognitive cycle: (sense
-
characterize - learn - adapt). The advent of
cognitive radio clearly portends a potential revolution in
wireless networking. It makes every aspect of wireless transmission and
reception
programmable. Devices can intelligently select the transmission format
and
media access technology, while all these characteristics are
software-reconfigurable. Most importantly,
devices equipped with cognitive radio can constantly monitor the
spectrum and discover how the
spectrum is being used. By dynamically
reconfiguring it to transmit in a way that does not interference with
existing
users, cognitive software radio allows exploitation the portion of
spectrum
that is allocated but unused. This creates additional capacity and
revenue from
existing spectrum, and addressing spectrum scarcity problem. The
concept of cognitive radio has received enormous attention from both
government (FCC, DARPA, NSF, ARMY, ONR) and major industrial
sources. In addition, the introduction of cognitive radio
could
potentially restructure the industry, significantly
increasing
the role of software in devices, and the role of end-devices in system
and networking.