A Second-Order Achievable Rate Region for Gaussian Multi-Access Channels via a Central Limit Theorem for Functions

作者：MolavianJazi Ebrahim^*; Laneman J Nicholas

来源：IEEE Transactions on Information Theory, 2015, 61(12): 6719-6733.

DOI：10.1109/TIT.2015.2492547

• Random coding and threshold decoding
• mutual information random variable
• power shell input
• change of measure
• delta method
• dispersion matrix
• second-order coding rate
• non-asymptotic achievability bounds
• low-latency communications

Motivated by the growing application of multi-access networks with stringent delay constraints, we investigate the Gaussian multiple-access channel (MAC) in the finite blocklength regime. By applying central limit theorem (CLT) approximations to non-asymptotic information-spectrum inner bounds, we obtain second-order achievable rate regions for the Gaussian MAC with a positive average error probability and per-codeword power constraints. Our achievability results use spherical inputs uniformly distributed on the power shells, which lead to summations of dependent information random variables. However, we conduct the analysis through a convenient yet powerful form of the CLT, called the CLT for functions.

• 出版日期2015-12