NOC4SC: A Bandwidth-Efficient Multi-User Semantic Communication Framework for Interference-Resilient Transmission

TL;DR

This paper introduces NOC4SC, a novel semantic communication framework that enables interference-resilient, bandwidth-efficient multi-user transmission using shared encoders and adaptive deep learning techniques.

Contribution

It presents a new non-orthogonal semantic communication scheme with adaptive SNR modulation and shared transformers, improving multi-user interference mitigation and spectral efficiency.

Findings

Achieves performance comparable to DeepJSCC-PNOMA

Outperforms existing multi-user SemCom methods

Effectively mitigates inter-user interference

Abstract

With the explosive growth of connected devices and emerging applications, current wireless networks are encountering unprecedented demands for massive user access, where the inter-user interference has become a critical challenge to maintaining high quality of service (QoS) in multi-user communication systems. To tackle this issue, we propose a bandwidth-efficient semantic communication paradigm termed Non-Orthogonal Codewords for Semantic Communication (NOC4SC), which enables simultaneous same-frequency transmission without spectrum spreading. By leveraging the Swin Transformer, the proposed NOC4SC framework enables each user to independently extract semantic features through a unified encoder-decoder architecture with shared network parameters across all users, which ensures that the user's data remains protected from unauthorized decoding. Furthermore, we introduce an adaptive NOC and SNR Modulation (NSM) block, which employs deep learning to dynamically regulate SNR and generate approximately orthogonal semantic features within distinct feature subspaces, thereby effectively mitigating inter-user interference. Extensive experiments demonstrate the proposed NOC4SC achieves comparable performance to the DeepJSCC-PNOMA and outperforms other multi-user SemCom baseline methods.