Coset codes for communicating over non-additive channels

Abstract: We present a case for the use of codes possessing algebraic closure properties - coset codes - in developing coding techniques and characterizing achievable rate regions for generic multi-terminal channels. In particular, we consider three diverse communication scenarios - $3-$user interference channel (many-to-many), $3-$user broadcast channel (one-to-many), and multiple access with distributed states (many-to-one) - and identify non-additive examples for which coset codes are analytically proven to yield strictly larger achievable rate regions than those achievable using iid codes. On the one hand, our findings motivate the need for multi-terminal information theory to step beyond iid codes. On the other, it encourages current research of linear code-based techniques to go beyond particular additive communication channels. Detailed proofs of our results are available in [1]-[3].