Parrino Stefano, Peruzzi Giacomo, Pozzebon Alessandro
Department of Information Engineering and Mathematics, University of Siena, 53100 Siena, Italy.
Sensors (Basel). 2021 May 29;21(11):3772. doi: 10.3390/s21113772.
The narrowband Internet-of-Things (NB-IoT) communication standard is gaining momentum within the big picture of the Internet-of-Things (IoT) owing to its capabilities of ensuring pervasive and wide coverage while limiting power consumption. Therefore, it turns out to be a valuable enabling technology within a considerable number of applications. Apart from traditional remote monitoring and data acquisition purposes where comparable Low Power Wide Area Network (LPWAN) facilities have ruled for years, NB-IoT can potentially carve out space within specific alcoves in which low latency, low power, high data-rates and ubiquitous coverage are fundamentals requirements. Long term asset tracking definitely falls within such niches, and in particular NB-IoT can become a valuable alternative to be exploited by both replacing the conventional Global Position System (GPS) system, or supporting it. To this end, this paper proposes an innovative tracking system prototype for asset shipping which relies on two enabling technologies: GPS and NB-IoT. While position transmission is always put into effect via NB-IoT, it can be fetched by resorting to both GPS (like a standard tracker) or NB-IoT (thus establishing a GPS-less method). As a result, two localization techniques are arranged: the former one is preciser but energy hungrier, while the latter one is coarser but more low power. Such working principles were successfully tested on the field by means of two road tests in as much itineraries. Tests results are in agreement with the expectations underlying the two working principles since the finer one provides a more accurate tracking. In addition, a consumption analysis was also performed aiming at assessing the prototype lifetime. Finally, tests pursuing the assessment of the tracking error were carried out underling the fact that it strongly depends on the geographic deployment of NB-IoT towers.
窄带物联网（NB-IoT）通信标准因其在确保广泛覆盖且限制功耗方面的能力，在物联网（IoT）的大框架内正获得越来越大的发展势头。因此，它在众多应用中成为一项有价值的使能技术。除了传统的远程监测和数据采集用途（多年来类似的低功耗广域网（LPWAN）设施一直占据主导）外，NB-IoT有可能在特定领域开辟空间，在这些领域中，低延迟、低功耗、高数据速率和无处不在的覆盖是基本要求。长期资产跟踪肯定属于此类细分领域，特别是NB-IoT可以成为一种有价值的替代方案，既可以替代传统的全球定位系统（GPS），也可以对其提供支持。为此，本文提出了一种用于资产运输的创新跟踪系统原型，该原型依赖于两项使能技术：GPS和NB-IoT。虽然位置传输始终通过NB-IoT来实现，但可以通过GPS（像标准跟踪器那样）或NB-IoT（从而建立一种无GPS方法）来获取位置信息。结果，安排了两种定位技术：前者更精确但能耗更高，而后者更粗略但功耗更低。通过在两条行程中的两次道路测试，这些工作原理在实地得到了成功测试。测试结果与这两种工作原理的预期相符，因为更精确的那种提供了更准确的跟踪。此外，还进行了功耗分析，旨在评估原型的使用寿命。最后，进行了旨在评估跟踪误差的测试，这突出了跟踪误差很大程度上取决于NB-IoT基站的地理布局这一事实。
