1. Introduction, Recent Results, and Challenges in Wireless Information and Power Transfer

The first effort to transmit energy wirelessly with the purpose of doing so is attributed to N. Tesla at his laboratory in Long Island, New York, USA. Then, about 30 years after J. Maxwell had demonstrated the potentials in 1873 the conveyance of energy trough vacuum via electromagnetic waves, corroborated in principle 15 years later by H. Hertz. The current expansion of the WPT via radio frequency beam owes to William Brown in 1960s using microwave technology developed during the World War II. Wireless Power Transfer (WPT) is gaining traction in many application domains because it offers the possibility of batteryless operation and wireless charging. Although wireless charging frequently gets the attention of the media, batteryless operation can bring major benefits for the environment and the massive deployment of wireless sensors in the Internet of Things (IoT). The salient feature of harvesting energy from electromagnetic radiation allows to gather energy even from ambient sources. Interference exploitation can also form a useful recourse at the expense of quality of experience. This chapter provides an overview of simultaneous wireless information and power transfer (SWIPT) systems with a particular focus on emerging techniques associated with SWIPT. We explore various key design issues in the development of SWIPT assisted emerging wireless communications technologies including the ones related to 5G communications. Chapter also provides interesting future research ideas and directions for interesting researchers.