With the ever-increasing speed of technological advances, more and more objects are being connected to the Internet every day and the world is moving toward the next generation of the Internet, the so called Internet of Things (IoT). However, numerous challenges need to be addressed for the widespread adoption of the IoT paradigm. Energy scarcity is one of these challenges. Recently, the advent of energy harvesting has relaxed energy limitation concerns. Specifically, RF energy harvesting has attracted a large amount of research due to its clear advantages over other energy harvesting methods. Lately, the extensive research in the RF energy harvesting domain has led to the emergence of wireless powered communication networks (WPCNs), where energy-constrained users are powered by wireless energy transfer of an integrated energy and information access point referred to as a hybrid access point (HAP). In this article, we review the research conducted in the field of WPCN and discuss opportunities for further extensions of these networks. Looking from the IoT point of view, we also present some of the points that must be taken into account for impeccable operation of WPCN in the IoT environment.

中文翻译：

---

面向未来物联网的无线通信网络的发展

随着技术进步的不断提高，每天都有越来越多的对象连接到Internet，并且世界正朝着下一代Internet（即所谓的物联网（IoT））发展。然而，物联网范式的广泛采用需要解决许多挑战。能源短缺是这些挑战之一。近来，能量收集的出现已经放松了对能量限制的关注。具体而言，RF能量收集由于其相对于其他能量收集方法的明显优势而吸引了大量研究。最近，在射频能量收集领域的广泛研究导致了无线通信网络（WPCN）的出现，能量受限的用户通过集成的能量和信息访问点（称为混合访问点（HAP））的无线能量传输来供电。在本文中，我们回顾了在WPCN领域中进行的研究，并讨论了进一步扩展这些网络的机会。从物联网的角度来看，我们还提出了在物联网环境中无可挑剔的WPCN操作必须考虑的一些要点。