DTC Science and Technology Innovators Lecture Series
Thomas L. Marzetta
Nokia Bell Labs
Thursday, April 13, 2017
401/402 Walter Library
View webcast of this lecture (Webex format)
Edwin H. Armstrong invented wideband Frequency Modulation, arguably the first coded modulation scheme, in 1933 – fifteen years before the publication of Claude Shannon’s seminal paper, “A Mathematical Theory of Communication”. A purely analog wireless technology, Wideband FM has been estimated to perform as little as 5 dB from the Shannon limit. Modern digital technology enables coded modulation that takes us almost all the way to the Shannon limit, and it has produced amazingly flexible wireless systems at low cost. The ever increasing demand for greater spectral efficiency is being met by exploiting the spatial dimension through multiple antenna (MIMO: Multiple-Input, Multiple-Output) technology, and particularly in what is likely to be its ultimate embodiment, Massive MIMO. While Massive MIMO owes a great debt to Shannon theory, in its simplest and most robust form it entails linear multiplexing and de-multiplexing based on direct measurements of the propagation channels, and this alone accounts for hundreds or thousands of dB of improvement over scalar wireless channels. It is tempting to speculate on how Armstrong would use a MIMO link. The matrix counterpart to the FM signal is a unitary matrix as a function of continuous time. Such a signal could be employed in a non-coherent Point-to-Point MIMO link if an available flat channel spectrum were divided into parallel channels occupying disjoint frequency intervals. The entire processing chain for Matrix FM is analogous to its scalar counterpart: matrix pre-emphasis filter and mapping into an instantaneous frequency matrix, differential equation generation of the unitary signal matrix, an svd-based limiter, a matrix discriminator, and a matrix de-emphasis filter.
Thomas Marzetta was born in Washington, D.C. He received the PhD and SB in Electrical Engineering from Massachusetts Institute of Technology in 1978 and 1972, and the MS in Systems Engineering from University of Pennsylvania in 1973. After careers in petroleum exploration at Schlumberger-Doll Research and defense research at Nichols Research Corporation, he joined Bell Labs (then AT&T; now Nokia) in 1995 where he is currently a Bell Labs Fellow. Previously he directed the Communications and Statistical Sciences Department within the former Mathematical Sciences Research Center.
Dr. Marzetta is on the Advisory Board of MAMMOET (Massive MIMO for Efficient Transmission), an EU-sponsored FP7 project, and he was Coordinator of the GreenTouch Consortium’s Large Scale Antenna Systems Project. He has received awards including the 2015 IEEE Stephen O. Rice Prize, the 2015 IEEE W. R. G. Baker Award, and the 2013 IEEE Guglielmo Marconi Prize Paper Award. He was elected a Fellow of the IEEE in 2003, and he received an Honorary Doctorate from Linköping University in 2015.