Error Control for Terabit Links: Spatially-Coupled Staircase Codes

For the past two decades, the data transmission rates achieved by optical-fiber-based transport networks have increased exponentially, but this increase may soon reach a so-called "capacity crunch" as transmission systems approach fundamental information-theoretic limits. This project addresses a key technology---forward error correction, or "FEC"---that will enable tomorrow's low-cost Internet-enabling Tb/s/wavelength optical communication links and may hold off the capacity crunch for a while longer. The only way to operate a channel at a throughput near the fundamental "Shannon limit" is by implementing advanced FEC, as uncoded transmission is simply too inefficient. This makes FEC a key component of all modern communication systems. The high data rates achieved by modern optical communications systems (today pushing towards 400 Gb/s/wavelength and beyond) creates challenges not faced by designers of lower-rate systems. Thus, new research is needed to find to find error-correction schemes that, on the one hand, are highly efficient from an information-theoretic viewpoint and yet, on the other hand, are implementation friendly. Staircase codes are one such family: they operate at an excellent tradeoff point between coding performance and implementation complexity. In this project, we plan to study staircase codes and related spatially-coupled data communication schemes. This proposal has two fundamental aims and one practical one: (a) to increase our theoretical understanding of these codes; and (b) to increase the range of potential applications for these codes (for example, to combine them with higher-order modulation, or allow them to take advantage of soft information); and (c) to develop practical algorithms on real programmable hardware platforms. This project also has the important objective of training a new generation of specialists able to bring a rigorous information-theoretically sound approach to the design of future optical communication systems. The results of this work will enable the Tb/s/wavelength optical communication links required to support the Internet of the future.