Estimados,
 
Queremos invitarlos a la próxima sesión del Seminario de Control, en
nuestro horario habitual: miércoles de 13:30 a 15:00 hs. en en Salón de
Seminarios del IIE.

Esta sesión estará a cargo del Prof.  Ravi Mazumdar
Professor and University Research Chair
Department of Electrical and Computer Engineering
University of Waterloo, CANADA

Nos hablará de:

Non-convexity issues in optimal resource allocation in wireless 
networks



ABSTRACT
This talk will focus on the problem of resource allocation and 
scheduling in wireless networks.
In this context the inherent utility functions are non-concave. However, 
the current network optimization algorithms deal are only suited for the 
concave case. 
The non-convexity results in a duality gap and the fact that the KKT 
conditions do not hold.
In the talk I will discuss the consequences of non-convexity in 
designing distributed schemes. In particular, I will discuss the problem 
of joint power and rate allocation as well as the issues of scheduling 
multiple users that we term power scheduling focussing on the 
downlink. In the first part we will show how a good distributed 
algorithm can be developed and that the framework also provides us 
with the means of studying the optimality of scheduling (single user
(TDMA type) vs multi-user (CDMA type)) policies.
In the second part we will show how to solve a general multi-user 
scheduling problem when utilities are non-convex. By exploiting the 
framework of sub-differentials we show simple, distributed algorithms 
can be developed that yield substantial performance improvements 
while assuring some degree of fairness.

Biography: The speaker was educated at the Indian Institute of 
Technology, Bombay (B.Tech, 1977), Imperial College, London (MSc, 
DIC, 1978) and UCLA (PhD, 1983). 
He has served on the faculties of
Columbia University, NY (USA) and INRS-T`elecommunications, 
Montreal, Canada . From 1996-99 he held the Chair in Operational 
Research in the Dept of Math, University of Essex (UK) and was 
Professor of Electrical Engineering at Purdue University, West 
Lafayette, IN (USA) during 1999-2005. He is currently a University 
Research Chair Professor at the Department of ECE, University of 
Waterloo, Waterloo, Canada.
His research interests are in performance and design of high-speed 
networks, game theory and pricing and in applied probability and 
queueing.
He is a Fellow of the IEEE and the Royal Statistical Society and 
serves on the editorial board of the IEEE/ACM trans. on Networking 
and a guest editor for an upcoming Special Issue of the IEEE JSAC
devoted to optimization and pricing in networks.


Saludos,
Rafael
 ============================================
Rafael Canetti
 
Depto.de Control y Electrónica Industrial    Julio Herrera y Reissig 565
- Instituto de Ingeniería Eléctrica -               11300 Montevideo
      Facultad de Ingeniería                             URUGUAY
 
 Fax.:   +(598 2) 711 74 35
 Tel.:   +(598 2) 711 09 74
 e-mail: canetti@fing.edu.uy
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