Department of Electrical Engineering, City University of Hong Kong, Hong Kong 999077, China.
Sensors (Basel). 2023 Feb 28;23(5):2660. doi: 10.3390/s23052660.
Given the advantage of LoRaWAN private networks, multiple types of services have been implemented by users in one LoRaWAN system to realize various smart applications. With an increasing number of applications, LoRaWAN suffers from multi-service coexistence challenges due to limited channel resources, uncoordinated network configuration, and scalability issues. The most effective solution is establishing a reasonable resource allocation scheme. However, existing approaches are not applicable for LoRaWAN with multiple services with different criticalities. Therefore, we propose a priority-based resource allocation (PB-RA) scheme to coordinate multi-service networks. In this paper, LoRaWAN application services are classified into three main categories, including safety, control, and monitoring. Considering the different criticalities of these services, the proposed PB-RA scheme assigns spreading factors (SFs) to end devices on the basis of the highest priority parameter, which decreases the average packet loss rate (PLR) and improves throughput. Moreover, a harmonization index, namely HDex, based on IEEE 2668 standard is first defined to comprehensively and quantitively evaluate the coordination ability in terms of key quality of service (QoS) performance (i.e., PLR, latency and throughput). Furthermore, Genetic Algorithm (GA)-based optimization is formulated to obtain the optimal service criticality parameters which maximize the average HDex of the network and contribute to a larger capacity of end devices while maintaining the HDex threshold for each service. Simulations and experimental results show that the proposed PB-RA scheme can achieve the HDex score of 3 for each service type at 150 end devices, which improves the capacity by 50% compared to the conventional adaptive data rate (ADR) scheme.
鉴于 LoRaWAN 专用网络的优势，用户在一个 LoRaWAN 系统中实现了多种类型的服务，以实现各种智能应用。随着应用数量的增加，由于信道资源有限、网络配置不协调和可扩展性问题，LoRaWAN 面临多业务共存的挑战。最有效的解决方案是建立合理的资源分配方案。然而，现有的方法不适用于具有不同关键程度的多种服务的 LoRaWAN。因此，我们提出了一种基于优先级的资源分配（PB-RA）方案来协调多业务网络。在本文中，LoRaWAN 应用服务被分为三类，包括安全、控制和监控。考虑到这些服务的不同关键程度，所提出的 PB-RA 方案根据最高优先级参数为终端设备分配扩频因子（SF），从而降低平均分组丢失率（PLR）并提高吞吐量。此外，首次定义了一个基于 IEEE 2668 标准的协调指标，即 HDex，用于全面和定量地评估关键服务质量（QoS）性能（即 PLR、延迟和吞吐量）方面的协调能力。此外，基于遗传算法（GA）的优化被制定，以获得最佳服务关键参数，这些参数最大化网络的平均 HDex，并有助于在保持每个服务的 HDex 阈值的同时提高终端设备的容量。仿真和实验结果表明，所提出的 PB-RA 方案可以在 150 个终端设备上为每种服务类型实现 3 的 HDex 分数，与传统的自适应数据速率（ADR）方案相比，容量提高了 50%。
