Ultra-reliable and Low-latency Communication (URLLC) has the potential to support data traffic transmission in factory automation, telesurgery, and automatic driving, where the differential quality of service (QoS) requirements in different types of traffic should be considered. In this letter, a differential QoS oriented URLLC policy is investigated for achieving high energy-efficiency under the given delay tolerance. To characterize the system state, a queueing model under First-In-First-Out (FIFO) service discipline is implemented. Based on this model, a cross-layer approach is developed to analyze the average transmission power and delay by formulating the system state into a Markov chain. For solving the problem more efficiently, the states of similar behavior in the Markov chain are aggregated, based on which the approximate solution can be obtained with low complexity. Numerical results verified the theoretical analysis and good performance of the proposed approach.

中文翻译：

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FIFO 服务规则下 URLLC 的 QoS 差分调度：跨层方法


超可靠低延迟通信（URLLC）有潜力支持工厂自动化、远程手术和自动驾驶中的数据流量传输，其中应考虑不同类型流量的不同服务质量（QoS）要求。在这封信中，研究了一种面向差分 QoS 的 URLLC 策略，以在给定的延迟容忍度下实现高能效。为了表征系统状态，实施了先进先出 (FIFO) 服务规则下的排队模型。基于该模型，开发了一种跨层方法，通过将系统状态表示为马尔可夫链来分析平均传输功率和延迟。为了更高效地解决问题，马尔可夫链中相似行为的状态被聚合，基于此可以得到低复杂度的近似解。数值结果验证了该方法的理论分析和良好性能。