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arXiv · 1908.11419

On exact asymptotics of the error probability in channel coding: symmetric channels

Yücel Altuğ·Aaron B. Wagner
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Abstract

The exact order of the optimal sub-exponentially decaying factor in the classical bounds on the error probability of fixed-length codes over a Gallager-symmetric discrete memoryless channel with and without ideal feedback is determined. Regardless of the availability of feedback, it is shown that the order of the optimal sub-exponential factor exhibits a dichotomy. Moreover, the proof technique is used to establish the third-order term in the normal approximation for symmetric channels, where a similar dichotomy is shown to exist.

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Yücel Altuğ, Aaron B. Wagner. 2019-08-29. On exact asymptotics of the error probability in channel coding: symmetric channels. https://arxiv.org/abs/1908.11419

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