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arXiv · 2607.16600

Variable Rate Lossy Source-Channel Coding over Channels with Feedback

Timothy Liu·Fady Alajaji·Tamás Linder
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Abstract

A variable-rate lossy joint source-channel coding scheme for burst-noise communication channels with noiseless feedback is introduced. The scheme comprises a multi-stage channel optimized vector quantization system that dynamically allocates bits via a greedy algorithm among the variable-rate residual quantizers at each stage, based on the channel output sequence received at the encoder through the feedback link, thereby generalizing a prior fixed-rate scheme. Simulations over an $M$-th order Markov noise Polya contagion channel demonstrate that the proposed variable-rate scheme consistently outperforms the fixed-rate scheme, regardless of the channel bit error rate and noise correlation, achieving signal-to-noise ratio gains of up to about 4.5 dB.

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Timothy Liu, Fady Alajaji, Tamás Linder. 2026-07-18. Variable Rate Lossy Source-Channel Coding over Channels with Feedback. https://arxiv.org/abs/2607.16600

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