ICL-SEC: Iterative Cross-Layer Semantic Error Correction

2026-08-15

AI Summary

This study addresses the reliability deficiencies and performance limitations of non-iterative approaches in cross-layer error correction for semantic communications. We propose an iterative cross-layer semantic error correction framework that facilitates soft information exchange between channel and language models. By designing a Confirm-based prior update rule, the method effectively suppresses mask oscillation while ensuring cross-layer consistency and reliable interpretation. Experimental results demonstrate that the proposed framework reduces the bit error rate by two orders of magnitude compared to non-iterative baselines. Furthermore, multiple key performance metrics are significantly improved, achieving efficient semantic error correction and enhanced system robustness.

Abstract

Iterative decoding has been central to the success of modern channel coding, where reliability information is repeatedly exchanged across decoding components to approach fundamental performance limits. This paper brings the same principle to semantic error correction by proposing iterative cross-layer semantic error correction (ICL-SEC), a framework that closes the loop between physical-layer soft channel decoder and application-layer language-model-empowered semantic decoder. In the proposed framework, a soft-input soft-output channel decoder first produces bit-level posterior probabilities, from which word-level reliabilities are derived. Words deemed reliable are exposed to a masked language model as semantic context, while unreliable words are masked. The language model then produces contextual word likelihoods, which are leveraged to generate extrinsic bit-level priors and fed back to the channel decoder for the next iteration. This iterative refinement progressively expands the set of confidently recovered words. A key contribution is our Confirm prior-update rule: once a word is judged reliable, its bits are assigned deterministic priors with probability one in subsequent iterations, making the word fully resolved side information for both the channel decoder and the language model. This successive-confirmation mechanism prevents oscillatory unmask-mask behavior and yields a reliability interpretation consistent across layers. Simulations over text transmission demonstrates that ICL-SEC substantially outperforms both conventional channel decoding and non-iterative CL-SEC. In particular, the proposed Confirm scheme reduces the bit error rate by more than two orders of magnitude relative to non-iterative CL-SEC, while also significantly improving the other five performance metrics.

Problem

• Semantic Error Correction
• Iterative Decoding
• Cross-Layer Communication
• Channel Coding
• Language Model

Innovation

• Iterative Cross-Layer Semantic Error Correction
• Confirm Prior-Update Rule
• Soft-Input Soft-Output Channel Decoder
• Masked Language Model
• Successive Confirmation Mechanism