Semantic communication has emerged as a promising paradigm for improving transmission efficiency by conveying task-relevant semantics rather than raw data. Although recent studies have achieved notable gains in communication efficiency and average task performance, reliability remains a fundamental bottleneck in dynamic and uncertain environments. In particular, most existing designs are still optimized mainly for average-case behavior, while lower-tail performance under adverse transmission conditions remains insufficiently understood and inadequately protected. In this article, we present a unified perspective on reliable semantic communication beyond average performance. We first review three reliability-oriented design categories: channel-aware adaptation, robustness-oriented codec design, and hybrid automatic repeat request (HARQ)-based retransmission. We show that these approaches address reliability from complementary perspectives, but each still has inherent limitations. Motivated by these observations, we discuss two solution directions: robust adaptive semantic communication under imperfect CSI, and joint source-channel-check coding with adaptive retransmission for sample-level reliability enhancement. Finally, we outline several future research directions, including the joint design of robustness and retransmission, reliability metrics beyond averages, and compatibility with existing digital wireless networks.

翻译：语义通信通过传递与任务相关的语义而非原始数据，已成为提升传输效率的一种有前景的范式。尽管近期研究在通信效率和平均任务性能方面取得了显著进展，但在动态和不确定环境中，可靠性仍是根本性瓶颈。特别是，现有设计大多仍主要针对平均行为进行优化，而恶劣传输条件下的低尾性能尚未得到充分理解和有效保护。本文提出一个统一视角，探讨超越平均性能的可靠语义通信。我们首先回顾三类面向可靠性的设计方法：信道自适应、鲁棒性导向的编解码器设计以及基于混合自动重传请求（HARQ）的重传机制。研究表明，这些方法从互补角度解决可靠性问题，但各自仍存在固有局限性。基于上述观察，我们讨论两个解决方向：非完美信道状态信息下的鲁棒自适应语义通信，以及面向样本级可靠性增强的自适应重传联合信源信道校验编码。最后，我们展望若干未来研究方向，包括鲁棒性与重传的联合设计、超越平均的可靠性度量，以及与现有数字无线网络的兼容性。