We consider a multi-cell grant-free uplink Internet of Things (IoT) network where multiple types of ultra-reliable and low-latency communications (URLLC) services with hard deadlines coexist. A mathematical framework is proposed for characterizing the packet loss rate (PLR) of each service given the network topology. Particularly, we derive the collision probability of resource block (RB) selection and a lower bound of the successful decoding probability. In addition, we formulate and solve the RB consumption minimization problem subject to the PLR constraints and an efficient algorithm is proposed. Numerical results show that the gap between the lower bound and the simulations is quite small in the ultra reliable cases, and the proposed algorithm outperforms the existing benchmark scheme.

中文翻译：

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URLLC 中具有硬期限服务的多小区无赠款上行链路物联网网络


我们考虑一个多小区无授权上行物联网 (IoT) 网络，其中多种类型的超可靠和低延迟通信 (URLLC) 服务并存，且期限严格。提出了一个数学框架来表征给定网络拓扑的每个服务的丢包率（PLR）。特别地，我们推导了资源块（RB）选择的冲突概率和成功解码概率的下界。此外，我们制定并解决了PLR约束下的RB消耗最小化问题，并提出了一种有效的算法。数值结果表明，在超可靠的情况下，下界与模拟之间的差距相当小，并且所提出的算法优于现有的基准方案。