Ravi Narasimhan, UC Santa Cruz
Date : November 10, 2006 (Friday)
Time : 11:30 AM
Location : ECE 202, NJIT

About the Speaker

Ravi Narasimhan received the B.S. degree (with highest honors) in electrical engineering and the Certificate of Distinction from the University of California at Berkeley in 1995, and the M.S. and Ph.D. degrees in electrical engineering from Stanford University in 1996 and 2000, respectively.

From 2000 to 2004, he was involved in research and development for next-generation wireless systems at Marvell Semiconductor, Inc., Sunnyvale, CA, most recently as Senior Engineering Design Manager in the Signal Processing Department. In July 2004, he joined the faculty in the Electrical Engineering Department at University of California, Santa Cruz.

He is also an active consultant for the wireless industry. His research interests include multiple-input multiple-output (MIMO) systems, multicarrier modulation, and multiuser communication theory.

Dr. Narasimhan is a senior member of IEEE and a member of Phi Beta Kappa, Sigma Xi and Golden Key National Honor Society. He received the Warren Y. Dere Memorial Prize from University of California at Berkeley in 1995. He secured the first rank in the Ph.D. qualifying examination in electrical engineering at Stanford University. He also received the Best Student Paper Award for U.S. at the IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC), held in Boston, MA, September 1998.

His biography was selected for publication in "Who's Who in America" and "Who's Who in Science and Engineering". He is an editor for the KICS/IEEE Journal of Communications and Networks, a member of the technical program committee for the IEEE ICC 2007 Communication Theory Symposium, and co-chair for the Communication and Information Theory Symposium of IWCMC 2007.

About the Talk

The benefits of multiple antennas at both the transmitter and the receiver in a wireless link consist of increased reliability and data rates. As the signal-to-noise ratio (SNR) approaches infinity, there exists a tradeoff between reliability (diversity) and data rate (multiplexing). Such an asymptotic tradeoff is applicable to high SNRs, high data rates, correspondingly low error rates, and ideal channels.

In this talk, a new finite-SNR (nonasymptotic) framework is presented to analyze the diversity-multiplexing tradeoff in multiple-input multiple-output (MIMO) systems. Finite-SNR multiplexing and diversity gains are defined in the context of rate adaptation. Outage probability bounds, derived from random matrix theory, are used to estimate the diversity gain as a function of SNR and multiplexing gain. Diversity gains at realistic SNRs are significantly lower than high-SNR asymptotes. Relations among the finite-SNR framework, spectral efficiency, and minimum mean-square error (MMSE) estimation will be explored.