Signal Processing and MIMO for Miltimode Fiber Links

Multimode fibers (MMF) are often used in short haul optical networks owing to favourable geometries and inexpensive packaging costs. However, the performance of multimode fibers has been limited primarily by the presence of high modal dispersion owing to large core diameters. While electronic dispersion compensation methods improve the bandwidth-distance product of MMF, they do not utlilize the fundamental diversity present in the different modes of the multimode fiber. In this work, we draw from developments in communication theory and signal processing for wireless communication in order to motivate the use of multiple-input multiple-output signal processing concepts to enable high-data rates through MMFs. We develop theoretical models and propose signaling algorithms to improve data rates with multiple modulators and detectors, and experimentally verify the validity of the theory on a multimode fiber link. We further explore the applicability of this theory to other multimode waveguides and consider the design of specific electro-optic devices to maximize data rates in conjunction with signal processing.

Bio: Kumar Appaiah is a graduate student of Electrical and Computer Engineering at The University of Texas at Austin, USA. His research interests are primarily in communication theory and applications of signal processing for wireless and optical links. Prior to joining UT Austin, he earned a B.Tech. in Electrical Engineering and M.Tech. in Communication Engineering from IIT Madras.