Book excerpt: A deep dive into wireless energy transfer technologies for IoT networks In Wireless Energy Transfer: Towards Sustainable Zero-Energy IoT Networks, distinguished researchers Onel L. A. López and Hirley Alves deliver a robust discussion of massive wireless energy transfer and zero-energy, low-cost, Internet of Things networks. Moving beyond the basic theoretical background of the subject, the authors offer a deep analysis of the scenarios and requirements of wireless energy transfer. The book details novel powering schemes recently proposed to face the challenging requirements of the future Internet of Things, as well as a comprehensive review of sustainable IoT wireless networks. Wireless Energy Transfer explains why novel energy efficient solutions will be needed to address the sheer volume of devices currently forecasted to be used in the near future. It explores the challenges technologists and users will face as well as proposed solutions and future research directions. The authors also discuss: Thorough introductions to wireless energy transfer, including energy harvesting sources, radio frequency energy harvesting circuits, efficiency models, and architectures for wireless energy transfer powered IoT networks Comprehensive explorations of ambient radio frequency energy harvesting, including measurement campaigns, energy harvesting hardware prototypes, and performance analysis based on stochastic geometry Practical discussions of efficient schemes for massive wireless energy transfer, including energy beamforming, multi-antenna techniques, and distributed antenna systems Perfect for students and researchers in signal processing, communications, networking, and information theory, Wireless Energy Transfer: Towards Sustainable Zero-Energy IoT Networks will also earn a place in the libraries of students and practitioners in the fields of communication hardware and transceiver design.