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arXiv · 2504.07420

Emergency Communication: OTFS-Based Semantic Transmission with Diffusion Noise Suppression

Kexin Zhang·Xin Zhang·Lixin Li·Wensheng Lin·Wenchi Cheng·Qinghe Du
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Abstract

Due to their flexibility and dynamic coverage capabilities, Unmanned Aerial Vehicles (UAVs) have emerged as vital platforms for emergency communication in disaster-stricken areas. However, the complex channel conditions in high-speed mobile scenarios significantly impact the reliability and efficiency of traditional communication systems. This paper presents an intelligent emergency communication framework that integrates Orthogonal Time Frequency Space (OTFS) modulation, semantic communication, and a diffusion-based denoising module to address these challenges. OTFS ensures robust communication under dynamic channel conditions due to its superior anti-fading characteristics and adaptability to rapidly changing environments. Semantic communication further enhances transmission efficiency by focusing on key information extraction and reducing data redundancy. Moreover, a diffusion-based channel denoising module is proposed to leverage the gradual noise reduction process and statistical noise modeling, optimizing the accuracy of semantic information recovery. Experimental results demonstrate that the proposed solution significantly improves link stability and transmission performance in high-mobility UAV scenarios, achieving at least a 3dB SNR gain over existing methods.

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Kexin Zhang, Xin Zhang, Lixin Li, Wensheng Lin, Wenchi Cheng, Qinghe Du. 2025-04-10. Emergency Communication: OTFS-Based Semantic Transmission with Diffusion Noise Suppression. https://arxiv.org/abs/2504.07420

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