We characterize a two-phase transmission scheme for a vehicle-to-everything (V2X) network, designed for ultra-reliable low-latency communications (URLLC). In the proposed scheme, the user-plane latency period for the URLLC application is divided into two phases by a partitioning factor. First, we derive the signal to noise ratio (SNR) coverage probability of a test vehicular node in the network as a function of the partitioning factor. We also study the impact of interference on the system performance. We show that the proposed scheme performs better in terms of the service outage as compared to a broadcast-only protocol for small file sizes. On the contrary, resource partitioning proves detrimental for large file sizes. Then, for the noise-limited case, we study the trend of the optimal resource-partitioning factor with respect to the transmitted data-size and the density of the vehicular nodes in the network. This letter shows that the data-size has a larger impact on the information outage, as compared to the density of the vehicular nodes.

中文翻译：

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V2X 网络中 URLLC 的协作中继

我们描述了车辆到一切 (V2X) 网络的两相传输方案，专为超可靠低延迟通信 (URLLC) 而设计。在所提出的方案中，URLLC 应用程序的用户平面延迟周期被一个分区因子分为两个阶段。首先，我们将网络中测试车辆节点的信噪比 (SNR) 覆盖概率推导出为分区因子的函数。我们还研究了干扰对系统性能的影响。我们表明，与小文件大小的仅广播协议相比，所提出的方案在服务中断方面表现更好。相反，资源分区证明对大文件有害。然后，对于噪声限制的情况，我们研究了最佳资源分配因子相对于传输数据大小和网络中车辆节点密度的趋势。这封信表明，与车辆节点的密度相比，数据大小对信息中断的影响更大。