On this page you find the material for the ISIT tutorial http://www.isit2013.org/Tutorials/T2/ on “Spatial Coupling and the Threshold Saturation Phenomenon.”

The tutorial is in four parts. The first part deals with background material and introduces the concept of spatial coupling and its related threshold saturation phenomenon. In the second part we give three alternative characterization of the so-called area threshold, the threshold up to which spatially-coupled graphical models “work” under standard belief propagation. In the third part we talk about how spatially coupled systems can be analysed. To keep things simple, the first three parts only deal with coding and transmission over the binary erasure channel. In the last part we survey some of the many applications where spatial coupling has been applied successfully.

There are two versions of our material. The first version consists of the Keynote slides. These contain movies and animations but require that you can read the Keynote format. The second version is a printed PDF file. It does not contain animations but it contains additional comments and notes. We will continue to update this page with the always latest version. Feedback is highly appreciated and we apologise for any missing references in advance.

Once upon a time it was deemed to be difficult to construct coding schemes that allow reliable transmission close to capacity at low complexity. But these days we have several such schemes. How do they compare? I will discuss in particular polar codes and spatially coupled codes. Which wins when we consider their scaling behavior, their complexity, the achievable throughput, universality, or robustness? As we will see, much is known, but many questions are still open.