Bello Hilal, Xiaoping Zeng, Nordin Rosdiadee, Xin Jian
College of Communication Engineering, Chongqing University, Chongqing 400044, China.
Centre of Advanced Electronic & Communication Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, UKM Bangi, Selangor 43600, Malaysia.
Sensors (Basel). 2019 Jul 12;19(14):3078. doi: 10.3390/s19143078.
Wake-up radio is a promising approach to mitigate the problem of idle listening, which incurs additional power consumption for the Internet of Things (IoT) wireless transmission. Radio frequency (RF) energy harvesting technique allows the wake-up radio to remain in a deep sleep and only become active after receiving an external RF signal to 'wake-up' the radio, thus eliminating necessary hardware and signal processing to perform idle listening, resulting in higher energy efficiency. This review paper focuses on cross-layer; physical and media access control (PHY and MAC) approaches on passive wake-up radio based on the previous works from the literature. First, an explanation of the circuit design and system architecture of the passive wake-up radios is presented. Afterward, the previous works on RF energy harvesting techniques and the existing passive wake-up radio hardware architectures available in the literature are surveyed and classified. An evaluation of the various MAC protocols utilized for the novel passive wake-up radio technologies is presented. Finally, the paper highlights the potential research opportunities and practical challenges related to the practical implementation of wake-up technology for future IoT applications.
唤醒无线电是一种很有前景的方法，可缓解空闲监听问题，该问题会给物联网（IoT）无线传输带来额外功耗。射频（RF）能量收集技术使唤醒无线电能够保持深度睡眠状态，仅在接收到外部RF信号以“唤醒”无线电后才变得活跃，从而消除了执行空闲监听所需的硬件和信号处理，提高了能源效率。本文综述基于文献中先前的研究工作，聚焦于基于无源唤醒无线电的跨层、物理层和媒体访问控制（PHY和MAC）方法。首先，介绍了无源唤醒无线电的电路设计和系统架构。之后，对文献中关于RF能量收集技术的先前研究工作以及现有的无源唤醒无线电硬件架构进行了调研和分类。对用于新型无源唤醒无线电技术的各种MAC协议进行了评估。最后，本文强调了与未来物联网应用中唤醒技术实际实施相关的潜在研究机会和实际挑战。
