Semantic communication is deemed as a revolution of Shannon's paradigm in the six-generation (6G) wireless networks. It aims at transmitting the extracted information rather than the original data, which receivers will try to recover. Intuitively, the larger extracted information, the longer latency of semantic communication will be. Besides, larger extracted information will result in more accurate reconstructed information, thereby causing a higher utility of the semantic communication system. Shorter latency and higher utility are desirable objectives for the system, so there will be a trade-off between utility and latency. This paper proposes a joint optimization algorithm for total latency and utility. Moreover, security is essential for the semantic communication system. We incorporate the secrecy rate, a physical-layer security method, into the optimization problem. The secrecy rate is the communication rate at which no information is disclosed to an eavesdropper. Experimental results demonstrate that the proposed algorithm obtains the best joint optimization performance compared to the baselines.

翻译：语义通信被认为是第六代（6G）无线网络中对香农范式的一场革命。其目标并非传输原始数据，而是传输提取后的信息，接收端将尝试根据这些信息进行恢复。直观而言，提取的信息量越大，语义通信的延迟将越长。同时，更大的提取信息量将带来更精确的重构信息，从而提升语义通信系统的效用。低延迟和高效用是系统的理想目标，因此效用与延迟之间存在权衡。本文提出了一种针对总延迟与效用的联合优化算法。此外，安全性对于语义通信系统至关重要。我们将物理层安全方法中的保密速率引入优化问题。保密速率是指不会向窃听者泄露任何信息的通信速率。实验结果表明，与基准方法相比，所提算法获得了最优的联合优化性能。