Multi-hop Parallel Image Semantic Communication for Distortion Accumulation Mitigation
Bingyan Xie, Jihong Park, Yongpeng Wu, Wenjun Zhang, Tony Quek
TL;DR
The paper tackles distortion accumulation in multi-hop wireless image transmission for semantic communication by introducing Multi-hop Parallel Semantic Communication (MHPSC) with a parallel residual compensation link. It combines a coarse-to-fine residual compression pipeline—consisting of a DL residual compressor and adaptive arithmetic coding (AAC) guided by a learned residual distribution estimator—to transmit residuals with minimal bandwidth overhead. Key contributions include the residual estimation module modeling the residual distribution as a mixture of logistic components, a two-stream MHPSC architecture with a compensation path, and a staged training paradigm that enhances multi-hop robustness. Experimental results on the UDIS-D dataset show MHPSC outperforms existing semantic and traditional SSCC schemes under various SNRs, CBRs, and hop counts, with only a modest bandwidth increase, indicating strong practical potential for reliable multi-hop image transmission in 6G-type networks.
Abstract
Existing semantic communication schemes primarily focus on single-hop scenarios, overlooking the challenges of multi-hop wireless image transmission. As semantic communication is inherently lossy, distortion accumulates over multiple hops, leading to significant performance degradation. To address this, we propose the multi-hop parallel image semantic communication (MHPSC) framework, which introduces a parallel residual compensation link at each hop against distortion accumulation. To minimize the associated transmission bandwidth overhead, a coarse-to-fine residual compression scheme is designed. A deep learning-based residual compressor first condenses the residuals, followed by the adaptive arithmetic coding (AAC) for further compression. A residual distribution estimation module predicts the prior distribution for the AAC to achieve fine compression performances. This approach ensures robust multi-hop image transmission with only a minor increase in transmission bandwidth. Experimental results confirm that MHPSC outperforms both existing semantic communication and traditional separated coding schemes.
