Frank R. Kschischang
Frank R. Kschischang’s work in the area of digital communications and coding theory has had a profound impact both in advancing the theoretical understanding of these subjects and in using them to solve real-world problems. His 1991 doctoral thesis considered the application of lattices to digital communications. He cleverly employed nonbinary codes to construct a number of dense sphere-packing lattices, including the Kschischang-Pasupathy lattice, which is still the densest-known sphere-packing lattice configuration in a 36-dimensional Euclidean space. He also devised a remarkable multidimensional signal constellation-shaping technique that was incorporated as a part of the internationally standardized V.34 modem design. To accomplish such results in a strongly researched area is truly impressive. There are several areas where Kschischang’s contributions have been pivotal: his highly cited work on factor graphs, his innovations in the use of the nonlinear Fourier transform for the performance improvement of optical communication systems, the co-invention of staircase codes, and his development of the Koetter-Kschischang subspace codes, which is perhaps his most brilliant technical contribution. His subspace-coding approach for error control in random linearly coded networks, developed with Ralf Koetter, is not only a beautiful mathematical theory but a contribution with significant practical applications, such as network coding for internet transmission. Kschischang’s application of the Nonlinear Fourier Transform provides both a theoretical understanding of and practical algorithms for achieving transmission schemes that can potentially overcome distortion caused by optical fiber nonlinearities. Staircase codes are a class of high-performance, yet low-complexity error-correcting codes now adopted in a number of international optical communication standards. These examples demonstrate Kschischang’s talent for taking on key practical challenges that beset contemporary communication systems, developing new mathematical tools and frameworks of analysis, then applying them to provide highly effective solutions. This tight coupling of theory and practice is the hallmark of Kschischang’s research and is in the very best tradition of communication engineering.
An IEEE Fellow, Kschischang is a professor in the Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, Toronto, Ontario, Canada.