Lossless Source Coding in the Point to Point, Multiple Access, and Random Access Scenarios
This paper treats point to point, multiple access and random access lossless source coding in the finite blocklength regime. A random coding technique is developed, and its power in analyzing the third order coding performance is demonstrated in all three scenarios. Results include a third order optimal characterization of the Slepian Wolf rate region and a proof showing that for dependent sources, the independent encoders used by Slepian Wolf codes can achieve the same third order optimal performance as a single joint encoder. The concept of random access source coding, which generalizes the multiple access scenario to allow for a subset of participating encoders that is unknown a priori to both the encoders and the decoder, is introduced. Contributions include a new definition of the probabilistic model for a random access discrete multiple source, a general random access source coding scheme that employs a rateless code with sporadic feedback, and an analysis demonstrating via a random coding argument that there exists a deterministic code of the proposed structure that simultaneously achieves the third order optimal performance of Slepian Wolf codes for all possible subsets of encoders.
2019 IEEE International Symposium on Information Theory (ISIT)