Empowering Wireless Sensor Networks with RF Energy Harvesting

In the past few years Wireless Sensor Networks (WSNs) played a prominent role in the Information, Communication and Technology (ICT). With a vast number of applications in various emerging fields like the Internet of Things (IOT), Cyber Physical Systems, medical, agriculture, structural engineering, military, etc., it is moving towards dominancy in the future. But, the sensors, processors and communicating devices are backed up by the energy sources which are limited to provide energy. The energy efficiency is achieved to some level with energy efficient protocols. For the continuous operation of the system, a continuous source of energy is needed. Energy harvested systems provide a regular source of energy for the continued operation in WSN. A number of energy harvesting techniques are available to harvest energy from the environment namely, solar energy, RF energy, mechanical energy, thermal energy, vibrations, etc. In this paper, a detailed review of RF energy harvesting in WSN is presented explaining its technique, components, energy consumption and harvesting models, its merits and demerits.