A Comprehensive Review on Design of Energy Harvesting Antennas for Charging Low Power Devices

With the increase in low-power electronics applications such as the Internet of Things (IoT), wireless sensor networks, and wearable electronics, there is an increasing demand for renewable energy sources that go beyond conventional battery systems. In this context, radio frequency energy harvesting (RFEH) is emerging as a viable technology that allows for the harvesting of ambient electromagnetic energy with conversion into usable electrical energy. This review discusses the state-of-the-art in the area of energy harvesting antennas, including their design methodologies, performance metrics, and implementation issues. It reviews various antenna configurations applicable to energy harvesting, such as wideband, multiband, and fractal antennas and their integration with rectifying systems to form complete rectenna systems. Much progress has been made on various technical issues, including impedance matching methodologies, device performance improvements through optimization and miniaturization techniques for harvesting systems. Further, in the area of metamaterials, intelligent systems and hybrid energy harvesting technologies are emerging as possible solutions to the problems highlighted in this review of the available literature. The purpose of this review is to provide an account of most of the significant papers that have been published recently and to elucidate the current progress in this area, as well as to highlight persistent problems and possible future approaches for the development of efficient energy harvesting antennas for low-power devices.