Optimum Power Control at Finite Blocklength
Name
Polyanskiy_Optimum power.pdf
Size
568.83 KB
Format
Adobe PDF
Checksum (MD5)
22150d2b8811f1d609fd9639b8afbfcd
Author(s)
Yang, Wei
Caire, Giuseppe
Durisi, Giuseppe
Polyanskiy, Yury
Date Issued
August 2015
Journal
IEEE Transactions on Information Theory
Publisher
Institute of Electrical and Electronics Engineers (IEEE)
Citation
Yang, Wei, Giuseppe Caire, Giuseppe Durisi, and Yury Polyanskiy. “Optimum Power Control at Finite Blocklength.” IEEE Transactions on Information Theory 61, no. 9 (September 2015): 4598–4615.
Version
Author's final manuscript
Abstract
This paper investigates the maximal channel coding rate achievable at a given blocklength n and error probability ϵ, when the codewords are subjected to a long-term (i.e., averaged-over-all-codeword) power constraint. The second-order term in the large-n expansion of the maximal channel coding rate is characterized both for additive white Gaussian noise (AWGN) channels and for quasi-static fading channels with perfect channel state information available at both the transmitter and the receiver. It is shown that in both the cases, the second-order term is proportional to (n[superscript -1] ln n)[superscript 1/2]. For the quasi-static fading case, this second-order term is achieved by truncated channel inversion, namely, by concatenating a dispersion-optimal code for an AWGN channel subject to a short-term power constraint, with a power controller that inverts the channel whenever the fading gain is above a certain threshold. Easy-to-evaluate approximations of the maximal channel coding rate are developed for both the AWGN and the quasi-static fading case.
MIT Department
Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science
Terms of Use
Creative Commons Attribution-Noncommercial-Share Alike
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1109/tit.2015.2456175
