论文标题
Hybrid-Arq的信息年龄：统一的明确结果
Age of Information with Hybrid-ARQ: A Unified Explicit Result
论文作者
论文摘要
在及时性交流系统中提供及时的状态更新对于协助准确有效的决策至关重要。因此，分析信息时代的话题引起了新的研究兴趣。本文通过系统地分析在Release-16 5G New Radio（NR）中新标准化的两种类型的混合自动重复请求（HARQ）技术的AOI，即反应性HARQ和主动HARQ。在基于代码的状态更新系统下，具有非平凡的编码延迟，传输延迟，传播延迟，解码延迟和反馈延迟，我们分别得出了统一的封闭形式的平均AOI和反应性HARQ和积极主动的HARQ的平均峰值AOI表达式。基于获得的显式表达式，我们制定了一个AOI最小化问题，以研究有限的块长度（FBL）制度中年龄优化的代码块分配策略。通过案例研究和分析结果，我们从新鲜的信息角度从反应性HARQ和主动HARQ之间提供了比较见解。数值结果和优化解决方案表明，积极主动的HARQ从年龄绩效和系统鲁棒性中汲取了强度，从而有能力提供新的系统的新系统进步，以实现新鲜度 - 关键性 - 关键状态更新系统。
Delivering timely status updates in a timeliness-critical communication system is of paramount importance to assist accurate and efficient decision making. Therefore, the topic of analyzing Age of Information has aroused new research interest. This paper contributes to new results in this area by systematically analyzing the AoI of two types of Hybrid Automatic Repeat reQuest (HARQ) techniques that have been newly standardized in the Release-16 5G New Radio (NR) specifications, namely reactive HARQ and proactive HARQ. Under a code-based status update system with non-trivial coding delay, transmission delay, propagation delay, decoding delay, and feedback delay, we derive unified closed-form average AoI and average Peak AoI expressions for reactive HARQ and proactive HARQ, respectively. Based on the obtained explicit expressions, we formulate an AoI minimization problem to investigate the age-optimal codeblock assignment strategy in the finite block-length (FBL) regime. Through case studies and analytical results, we provide comparative insights between reactive HARQ and proactive HARQ from a perspective of freshness of information. The numerical results and optimization solutions show that proactive HARQ draws its strength from both age performance and system robustness, thus enabling the potential to provide new system advancement of a freshness-critical status update system.
