Onumanyi Adeiza J, Abu-Mahfouz Adnan M, Hancke Gerhard P
Department of Electrical, Electronic and Computer Engineering, University of Pretoria, Pretoria 0028, South Africa.
Council for Scientific and Industrial Research (CSIR), Pretoria 0001, South Africa.
Sensors (Basel). 2020 Nov 30;20(23):6837. doi: 10.3390/s20236837.
The Internet of Things (IoT) is an emerging paradigm that enables many beneficial and prospective application areas, such as smart metering, smart homes, smart industries, and smart city architectures, to name but a few. These application areas typically comprise end nodes and gateways that are often interconnected by low power wide area network (LPWAN) technologies, which provide low power consumption rates to elongate the battery lifetimes of end nodes, low IoT device development/purchasing costs, long transmission range, and increased scalability, albeit at low data rates. However, most LPWAN technologies are often confronted with a number of physical (PHY) layer challenges, including increased interference, spectral inefficiency, and/or low data rates for which cognitive radio (CR), being a predominantly PHY layer solution, suffices as a potential solution. Consequently, in this article, we survey the potentials of integrating CR in LPWAN for IoT-based applications. First, we present and discuss a detailed list of different state-of-the-art LPWAN technologies; we summarize the most recent LPWAN standardization bodies, alliances, and consortia while emphasizing their disposition towards the integration of CR in LPWAN. We then highlight the concept of CR in LPWAN via a PHY-layer front-end model and discuss the benefits of CR-LPWAN for IoT applications. A number of research challenges and future directions are also presented. This article aims to provide a unique and holistic overview of CR in LPWAN with the intention of emphasizing its potential benefits.
物联网（IoT）是一种新兴模式，它催生了许多有益且具有前瞻性的应用领域，比如智能电表、智能家居、智能工业和智慧城市架构等等。这些应用领域通常由终端节点和网关组成，它们常通过低功耗广域网（LPWAN）技术相互连接。LPWAN技术具有低功耗率，可延长终端节点的电池寿命，降低物联网设备的开发/采购成本，传输距离远，可扩展性强，不过数据速率较低。然而，大多数LPWAN技术常常面临一些物理（PHY）层挑战，包括干扰增加、频谱效率低下和/或数据速率低等问题，而认知无线电（CR）作为一种主要的PHY层解决方案，足以成为一种潜在的解决方案。因此，在本文中，我们探讨了将CR集成到LPWAN中以用于基于物联网的应用的潜力。首先，我们展示并讨论了一份详细的不同的最新LPWAN技术列表；我们总结了最新的LPWAN标准化机构、联盟和协会，同时强调了它们对在LPWAN中集成CR的倾向。然后，我们通过一个PHY层前端模型突出了LPWAN中CR的概念，并讨论了CR-LPWAN对物联网应用的好处。我们还提出了一些研究挑战和未来方向。本文旨在对LPWAN中的CR进行独特而全面的概述，以强调其潜在优势。
