Room AVW 2353
(301) 405 3661
Fax: (301) 314 9281
Tu 4:30 - 5:45 pm EST
Th 2:00 - 3:15 pm EST
Also by appointment
To provide a general understanding of the basic principles
which govern the design and operation of wireless communication
networks, with emphasis on the wireless link, media access control
and interference issues. We begin by considering the cellular
architecture model, frequency reuse, power control, handoff
and mobility tracking. We then consider wireless local area
networks, including a review of recently proposed standards.
Next, ad hoc networks will be studied with a focus on
routing/multicasting and \lq\lq capacity" notions. Principles of
of layer integration and energy efficiency will also be
addressed. The special cases of sensor networks and satellite
systems will be reviewed.
A mastery of Random Processes in Communication and Control
(ENEE 620 or equivalent) and Multiuser Communication (ENEE 625 or
equivalent) is expected. Further, a sound knowledge of Information
Theory (ENEE 721 or equivalent) will make all our cups runneth over.
The final grade for the course will be determined by a student's
- a midterm in-class written examination (30%);
- a term project (10% for proposal, 20% for final oral presentation
40% for final written report).
The midterm examination will be held in the last week
of October 2004 (sufficient
advance notice of the exact date will be provided).
The term project will have three components:
- a written proposal (due in the last week ofOctober 2004);
- an oral presentation (in the last week of class);
- a written project report (due on December 13, 2004).
Details will be provided later.
Please note: There will be no written in-class
December 18, 2004.
- Midterm examination: Tuesday, Nov. 9, 2004
Planned course topics
1. Introductory concepts
- Wireless medium (models, properties)
- Multiaccess channel
- Medium access control
- Interference and quality of service.
2. Cellular networks
- Basic architecture
- Frequency reuse
- Power control
- Mobility control - handoff
- Dynamic channel assignment
- Registration, paging, mobile IP.
3. Wireless local area networks
- Comparisons and contrasts with (ordinary) LANs
- IEEE 802.11
- Infrared systems.
4. Ad hoc networks (multihop)
- Notions of "link" and "graph"
- Layer interaction
- "Capacity" notions.
5. Energy efficiency
- Forms of energy consumption
- Effects of power control, MAC and routing/multicasting
- Limited energy supply.
6. Sensor networks
- Objectives and architectures
- Energy concerns
- Design approaches.
7. Satellite networks
- Modern satellite systems
- Onboard processing capabilities
- Satellite constellations
- Hybrid networks -- design and performance.
1. R. L. Cruz and A. V. Santhanam, ``Optimal
Scheduling and Power
Control in Multi-hop Wireless Networks
2. A. E. Gamal, J. Mammen, B. Prabhakar and D. Shah,
in Wireless Networks
Dr. Gerhard Kramer, Bell Labs
: Communication Models and
Information Theory for
Relay Channels with Transmit and Receive Constraints
: Friday, October 22, 2004
: 11:00 a.m.
: Room 2460, AVW
A relay network has a source terminal transmitting a
message to a destination terminal with the help of one or more relays.
Such a situation might occur in a multi-hop or sensor network where
there are several terminals that help each other transmit data.
We develop simple communication models for such networks, review
existing information theory for the models, and develop several
multi-hopping strategies, where by multi-hopping we mean that the
relays successively decode the message before it arrives at the
We show that the rates of these strategies are
optimal for certain wireless scenarios.
We extend the results to wider classes of problems, including relays
cannot transmit and receive at the same time. For this last case, we
that the best coding strategies use random, rather than predetermined,
1. Capacity Theorems for Wireless Relay
2. Information–theoretic Multi–hopping for
3. Models and Theory for Relay Channels
with Receive Constraints
4. Cooperative Strategies and Capacity
Theorems for Relay Networks
Dr. Piyush Gupta, Bell Labs
Scheduling with Service Differentiation in
Wireless Data Networks
: Friday, November 5, 2004
: 11:00 a.m.
: Room 3120, CSIC
Recent years have seen tremendous
growth in wireless local area
networking. An important issue in such networks is that of distributed
scheduling. Unlike in cellular networks, there is no central agent
that coordinates the medium access of all users in a cell. This leads
to significant throughput degradation due to multi-user contention.
Existing approaches, such as Slotted Aloha or IEEE 802.11, also fail
to provide differentiated service to users. We describe a class of
new distributed scheduling algorithms, Regulated Contention Medium
Access Control (RCMAC), which provides dynamic prioritized access to
users for service differentiation. Furthermore, by regulating
multi-user contention, RCMAC achieves higher throughput when traffic
is bursty, as is typically the case. We also discuss ongoing work to
extend RCMAC to multi-hop wireless networking scenarios, such as
ad hoc networks and sensor networks.
(Based on joint work with Yogesh Sankarasubramaniam (G.Tech.) and
Alexander Stolyar (Bell Labs).)
1. Random-Access Scheduling with Service
2. The Capacity of Wireless Networks
3. Critical Power for Asymptotic Connectivity in
3. Dr. Vijay Subramanian, Motorola
: Convergence and Optimality of Opportunistic Scheduling
: Friday, November 19, 2004
: 11:00 a.m.
: Room 2460, AVW
With an abstraction of serving
rate-adaptive sources on a
broadcast-type wireless channel as a utility maximization problem, it is
shown how one can design many intuitive online scheduling policies based
upon the feedback that one obtains at the scheduler. Using a stochastic
approximation argument it is then shown that the constructed algorithms
converge to optimal solutions of the utility maximization problem over
different sets which critically depend on the quality of the feedback
We then apply the theory developed above to the downlink in a CDMA based
wireless network. In terms of operational variables the problem is to
select a subset of the users for transmission at each transmission
opportunity and for each of the users selected, to choose the
and coding scheme, transmission power, and number of codes used. We
refer to this combination as the physical layer operating point (PLOP).
Each PLOP consumes different amounts of code and power resources.
Thus, the task is to pick the ``optimal'' PLOP taking into account both
system-wide and individual user resource constraints that can arise in a
practical system. Using an information theoretic model for the
achievable rate per code results in a tractable convex optimization
problem. By exploiting the structure of this problem, we give
algorithms for finding the optimal solution with geometric convergence.
We also use insights obtained from the optimal solution to construct
low complexity near optimal algorithms that are easily implementable.
Numerical results comparing these algorithms are also given.
1. Optimality of Certain Channel Aware Scheduling
2. Joint Scheduling and Resource Allocation in CDMA
3. Presentation Slides
Dr. Venu Veeravalli, NSF (University of Illinois)
: Friday, December 10, 2004
: Room 2460, AVW
There is no required textbook for the course. Material
for the lectures will be extracted from
books and technical articles in journals which are
The student is expected
be self-driven and
brimming with initiative. The field of wireless communication
networks is vast, but the lecture-time is short. The student is,
therefore, expected -- of her or his own volition -- to assimilate,
assimilate, assimilate ... from the material below.
The contents of the lectures, by necessity, will be neither
complete nor exhaustive.
. A. Goldsmith, Wireless Communications
(to appear, 2005)
. K. Pahlavan and A.H. Levesque, Wireless Information Networks
John Wiley & Sons, New York (NY) (1995).
. K. Pahlavan and P. Krishnamurthy, Principles of Wireless
Prentice-Hall PTR (NJ) (2002).
. T.S. Rappaport, Wireless Communications: Principles &
Prentice-Hall, Upper Saddle River (NJ) (1996).
. C. Siva Ram Murthy and B.S. Manoj, Ad Hoc Wireless Networks:
Architectures and Protocols
, Prentice-Hall PTR (NJ) (2004).
. R. Steele, Mobile Radio Communications
IEEE Press, New York (NY) (1995).
. G. L. Stüber, Principles of Mobile Communication
Second Edition, Kluwer Academic, Boston (MA) (2001).
. D. Tse and P. Viswanath, Fundamentals of Wireless
(draft dated August 13, 2004)
B. Journal articles, Conference
An overdose of information can be found in the following
IEEE/ACM Transactions on Networking
IEEE Transactions on Communications
IEEE Journal on Selected Areas in Communications
IEEE Transactions on Information Theory
IEEE Transactions on Computers
IEEE Transactions on Vehicular Technology
IEEE Communications Magazine
IEEE Personal Communications Magazine
IEEE Wireless Communications
IEEE Network -- The Magazine of Computer Communications
Journal of the Association for Computing Machinery
Journal of High Speed Networks
ACM Journal on Wireless Networks
Computer Networks and ISDN
Proceedings of the IEEE
International Conference on Communications (ICC)
Vehicular Technology Conference (VTC)
IEEE International Symposium on Information Theory (ISIT).
You are encouraged
visit Andrea Goldsmith's
for her Spring 2004 course at Stanford University
on "Advanced Topics in Wireless Communications."
It contains a well-organized and rich collection
of relevant reference material.