# Low Power Wide Area Network, Cognitive Radio and the Internet of Things: Potentials for Integration
CR refers to an intelligent radio system developed primarily to address issues pertaining to inefficient spectral utilization. It was conceived following the relatively recent unavailability of radio spectrum for the deployment of new wireless technologies. CR aims to take advantage of unused (free) bands towards improving the user's perceived quality of service (QoS) over different communication networks. There are several innovative CR technologies presently under development, which may greatly complement both existing and new LPWAN technologies; thus, it is pertinent to present an overview of these efforts and vision as it relates to enhancing different IoT applications. Thus, in this article, we discuss independently both LPWAN and CR features and technologies as a foundation for the potential integration of CR in LPWAN. We highlight the concept of CR enabled LPWAN systems, termed CR-LPWANs. The potentials of CR-LPWAN systems are discussed along with the documentation of specific research challenges, which may limit the realization of CR-LPWAN systems. It is hoped that these research directions will spur researchers and LPWAN developers alike towards developing future ideas that will drive the next generation of IoT devices. Summarily, the present article contributes as follows:  
1. It presents insights and a recent overview regarding the use of CR in LPWAN. In particular, the use of CR as a potential solution to some known LPWAN problems is considered. 2. In addition to discussing the concept of CR-LPWAN, the present article provides a framework for integrating CR and LPWAN modules into a possible functional unit. It describes the front-end of a generic CR-LPWAN system describing how the interlink of each module may contribute to the support of effective CR-LPWAN systems. 3. We identify specific challenges that may mitigate against the realization of functional CR-LPWAN systems. Specifically, new insights are provided into different research challenges that require the use of adaptive CR technologies in LPWAN transceivers. An up-to-date information is provided pertaining to the development and standardization of LPWAN systems in general. These include the provision of a summary concerning the origin of different LPWAN technologies, and an update regarding the different standard organizations and special groups involved in LPWAN development. An updated list of different LPWAN technology developers is provided with focus on their potential/adoption of CR technology. The use of CR is also discussed with regards to the general IoT architecture and the different challenges in this direction. Essentially, this article provides insights and future research considerations with regards to the concept of CR in LPWAN technologies, which may interest readers aiming to explore this new research trend. The rest of this article is structured as follows: related survey articles are discussed in Section 2. An overview of LPWAN is provided in Section 3, with a similar overview of CR presented in Section 4. Then, we discuss the concept of CR-LPWAN in Section 5 where we look at its general concept via a PHY-layer front-end model, network architecture and support protocols. Section 6 presents the potential benefits of CR-LPWAN for IoT, whereas Section 7 discusses challenges and future research directions. We conclude in Section 8.