论文标题
在1-迫切的重传urllc服务中
On 1-Persistent Retransmission in Grant-free Access for URLLC Service
论文作者
论文摘要
超级可信和低延迟通信（URLLC）是5G新广播的三个主要应用程序方案之一，该方案具有严格的延迟和可靠性要求。已经为上行链路URLLC服务提出了基于竞争的赠款（GF）访问协议，例如反应性，K-重复和积极主动。在GF访问中，用户设备（UE）在传输不成功后立即重新安排数据包，以便满足延迟要求。以反应性为例，本文研究了1-持续重传（1-pr）对用户平面延迟分布的影响。我们将尝试在每个迷你插槽中发送数据包的UE数量作为尝试率。我们表明，1PR使数据包在重传中看到的尝试速率比第一个变速箱中的数据包所看到的。结果，重新传输的成功概率低于第一个传输的概率。基于此观察结果，我们得出了用户平面延迟的分布，这也考虑了排队过程所产生的延迟。我们证明，是否在分析中包括1-PR和排队过程的效果会对延迟分布的预测准确性产生重大影响。
Ultra-reliable and low-latency communication (URLLC) is one of three major application scenarios of the 5G new radio, which has strict latency and reliability requirements. Contention-based grant-free (GF) access protocols, such as Reactive, K-Repetition, and Proactive, have been proposed for uplink URLLC service. In the GF access, user equipment (UE) resends packet immediately after an unsuccessful transmission such that the latency requirement can be satisfied. Taking Reactive as an example, this paper studies the impact of 1- persistent retransmission (1-pR) on the distribution of user-plane delay. We define the number of UEs that try to send packets in each mini-slot as attempt rate. We show that the 1-pR makes the attempt rate seen by the packet in retransmission larger than that seen by the packet in the first transmission. As a result, the successful probability of retransmission is lower than that of the first transmission. Based on this observation, we derive the distribution of user-plane delay, which also takes into account the delay incurred by queueing process. We demonstrate that whether to include the effect of 1-pR and queueing process in the analysis would have a significant impact on the prediction accuracy of delay distribution.
