🤖 AI Summary
To address the challenge in semantic communication where diverse downstream tasks hinder semantic representations from simultaneously achieving bandwidth efficiency and task adaptability, this paper proposes a task-adaptive diffusion model framework. At the transmitter, a lightweight, universal semantic representation is encoded; at the receiver, task-specific textual prompts—tailored to classification, detection, or reconstruction—are generated and fed back. The transmitter then dynamically enhances transmission of critical semantic components via attention mechanisms. This work pioneers the integration of controllable diffusion models with a bidirectional, task-driven feedback mechanism in semantic communication, enabling bandwidth-aware, on-demand semantic regeneration and deep semantic compression. Experiments demonstrate that, under high compression ratios, the proposed method achieves a 12.7% average performance gain across multiple tasks over baseline approaches, significantly improving both semantic fidelity and task accuracy.
📝 Abstract
Semantic communications represent a new paradigm of next-generation networking that shifts bit-wise data delivery to conveying the semantic meanings for bandwidth efficiency. To effectively accommodate various potential downstream tasks at the receiver side, one should adaptively convey the most critical semantic information. This work presents a novel task-adaptive semantic communication framework based on diffusion models that is capable of dynamically adjusting the semantic message delivery according to various downstream tasks. Specifically, we initialize the transmission of a deep-compressed general semantic representation from the transmitter to enable diffusion-based coarse data reconstruction at the receiver. The receiver identifies the task-specific demands and generates textual prompts as feedback. Integrated with the attention mechanism, the transmitter updates the semantic transmission with more details to better align with the objectives of the intended receivers. Our test results demonstrate the efficacy of the proposed method in adaptively preserving critical task-relevant information for semantic communications while preserving high compression efficiency.