Receiver Design for Space-Time Coded Systems

Dr. Costas N. Georghiades

J.W. Runyon Jr. Professor and
Director, Telecommunications and Signal Processing Group
Electrical Engineering Department
Texas A&M University
College Station, TX 77843-3128

Friday, March 2nd, 3:00 PM, ENS 302

georghia@ee.tamu.edu

Abstract

Most curret work on detecting space-time coded signals assumes that the fading channel matrix between multiple transmit and multiple receive antennas is perfectly known. Additionally, it is assumed that fading is perfectly static over the received data block. The assumption, of course, is that the channel can be estimated through the use of periodically inserted pilot-symbols. The channel estimate can then be used by the same receiver that assumes perfect channel knowledge in place of the exact channel. These receivers, although simple to implement, do not achieve the optimum performance, since, by making use of only the pilot symbols to estimate the channel, they ignore the information contained in the modulated data.

In this talk we will look at receiver structures that do not assume channel knowledge or a static fading channel. They include the maximum-likelihood (ML), an EM-formulation of it, the generalized ML, and an efficient implementation of it that makes use of the Viterbi algorithm when the Alamouti scheme is used. In the end, time permitting, I will summarize some further results of work in the space-time coding area.

Biography

Costas N. Georghiades received the B.E. degree with distinction from the American University of Beirut in June 980, and the M.S. and D.Sc. degrees from Washington University in May 1983 and May 1985, respectively, all in Electrical Engineering. Since September 1985 he has been with the Electrical Engineering department at Texas A&M University, where he is a Professor and holder of the J.W. Runyon, Jr. Endowed Professorship. His general interests are in the application of information, communication and estimation theories to the study of communication systems.

Dr. Georghiades is a Fellow of the IEEE and a registered Professional Engineer in Texas. Over the years, he served in editorial positions for various IEEE journals, including the Transactions on Information Theory, the Transactions on Communications, the Journal on Selected Areas in Communications, and the IEEE Communication Letters. He has been involved in organizing a number of conferences, including as Technical Program Chairman for the 1997 IEEE Communication Theory Mini Conference, and as Technical Program Chair for the 1999 IEEE Vehicular Technology Conference. He currently serves as Chair of the Communication Theory Symposium within Globecom 2001, and as Technical Program Chair for the 2001 Communication Theory Workshop.

A list of Telecommunications and Signal Processing Seminars is available at from the ECE department Web pages under "Seminars". The Web address for the Telecommunications and Signal Processing Seminars is http://anchovy.ece.utexas.edu/seminars