LoRa/LoRaWAN is growing rapidly as an underlying technology for the Internet of Things because of its long-range connectivity and low power. However, its limited scalability, owing to spread spectrum–based modulation and contention-based medium access control, impedes its use in emerging massive applications. In this study, we propose a downlink transmission scheme for enhancing the scalability of LoRa networks. The proposed scheme consists of two mechanisms. First, a modulation parameter is adjusted using the different transmission power limitations between the gateways and end devices to reduce downlink duration. Second, the timing of downlink traffic is selected based on uplink traffic concentration analysis. The proposed scheme reduces the uplink failure, and consequently, allows more end devices to participate in the network. The simulation results show that the proposed scheme is superior to the standard protocol in terms of the packet delivery ratio.

中文翻译：

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用于增强 LoRa 网络可扩展性的占用平衡下行链路传输

LoRa/LoRaWAN 作为物联网的底层技术正在迅速发展，因为它具有远程连接性和低功耗。然而，由于基于扩频的调制和基于竞争的媒体访问控制，其有限的可扩展性阻碍了其在新兴的大规模应用中的使用。在这项研究中，我们提出了一种用于增强 LoRa 网络可扩展性的下行链路传输方案。提议的方案由两种机制组成。首先，使用网关和终端设备之间的不同传输功率限制来调整调制参数以减少下行链路持续时间。其次，根据上行流量集中度分析选择下行流量的时序。所提出的方案减少了上行链路故障，从而允许更多终端设备参与网络。