Finite block-length gains in distributed source coding

A new coding scheme for the distributed source coding problem for general discrete memoryless sources is presented. The scheme involves a two-layered coding strategy, the first layer code is of constant finite block-length whereas the second layer contains codes of block-length approaching infinity. It is argued that small block-length codes preserve correlations between sources more efficiently, while suffering rate-loss in a point-to-point compression perspective. Consequently, there is a sweet-spot for the length of the code. An achievable rate-distortion region is characterized using single-letter distributions. It is shown that this region strictly contains previous known achievable rate-distortion regions for the distributed source coding problem.