标题： 如此及时，却又如此过时：时钟漂移在实时系统中的影响 显示英文标题

标题： So Timely, Yet So Stale: The Impact of Clock Drift in Real-Time Systems

摘要： 本文研究了实时通信系统中状态更新数据包的及时投递问题，在该系统中发送方通过不可靠信道将源生成的状态更新发送至接收方。发送和接收的数据包的时间戳分别使用位于发送方和接收方的独立时钟测量。为了考虑这两个时钟之间可能存在的时钟漂移，我们同时考虑确定性漂移和概率性漂移场景。我们分析了系统在信息年龄（AoI）方面的性能，并在两种时钟漂移模型下推导出AoI分布和平均AoI的闭式表达式。此外，我们通过解析和数值结果探讨了关键系统参数对平均AoI的影响。 显示英文摘要

摘要： In this paper, we address the problem of timely delivery of status update packets in a real-time communication system, where a transmitter sends status updates generated by a source to a receiver over an unreliable channel. The timestamps of transmitted and received packets are measured using separate clocks located at the transmitter and receiver, respectively. To account for possible clock drift between these two clocks, we consider both deterministic and probabilistic drift scenarios. We analyze the system's performance regarding the Age of Information (AoI) and derive closed-form expressions for the distribution and the average AoI under both clock drift models. Additionally, we explore the impact of key system parameters on the average AoI through analytical and numerical results.