LoRaWAN enables massive connectivity for Internet-of-Things applications. Many published works employ stochastic geometry to derive outage models of LoRaWAN over fading channels assuming fixed transmit power and distance-based spreading factor (SF) allocation. However, in practice, LoRaWAN employs the Adaptive Data Rate (ADR) mechanism, which dynamically adjusts SF and transmit power of nodes based on channel state. The community addressed the performance of ADR using simulations, but analytical models have not been introduced. In this letter, we seek to close this gap. We build over an analytical LoRaWAN model to consider the performance of steady-state ADR-enabled LoRaWAN. We derive outage expressions and an optimization procedure to maximize the number of users under reliability constraints. Results show that power allocation reduces interference and improves network capacity while reducing average power.

中文翻译：

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启用单小区自适应数据速率的 LoRaWAN 的性能分析

LoRaWAN 支持物联网应用的大规模连接。许多已发表的作品采用随机几何来推导 LoRaWAN 在衰落信道上的中断模型，假设固定的发射功率和基于距离的扩频因子 (SF) 分配。然而，在实践中，LoRaWAN 采用​​了自适应数据速率 (ADR) 机制，该机制根据信道状态动态调整节点的 SF 和发射功率。社区使用模拟解决了 ADR 的性能问题，但尚未引入分析模型。在这封信中，我们试图缩小这一差距。我们构建了一个分析性 LoRaWAN 模型，以考虑支持稳态 ADR 的 LoRaWAN 的性能。我们推导出中断表达式和优化程序，以在可靠性约束下最大化用户数量。