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arXiv · 2601.07472

Secure Joint Source-Channel Coding for the AWGN Channel with Feedback: A Finite Blocklength Analysis

Sheng Su·Yuhan Yang·Chao Qi·Xuan He·Bin Dai·Xiaohu Tang
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Abstract

In the literature, it has been shown that the secrecy capacity of the additive white Gaussian noise (AWGN) wiretap channel with noise-free feedback equals the capacity of the same model without secrecy constraint, and the classical Schalkwijk-Kailath (SK) scheme achieves the secrecy capacity. In this paper, we show that in finite blocklength regime, the SK scheme is not optimal, and propose a modified SK scheme which may perform better than the classical one. Besides this, this paper establishes a finite blocklength converse for the AWGN wiretap channel with feedback, which can also be viewed as a converse for the same model without secrecy constraint. To the best of the authors' knowledge, this is the first paper to address such a problem, and the results of this paper are further explained via numerical examples.

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Sheng Su, Yuhan Yang, Chao Qi, Xuan He, Bin Dai, Xiaohu Tang. 2026-01-12. Secure Joint Source-Channel Coding for the AWGN Channel with Feedback: A Finite Blocklength Analysis. https://arxiv.org/abs/2601.07472

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