SELF-POWERED AUTONOMOUS RECONFIGURABLE INTELLIGENT SURFACES USING WIDE RADIO FREQUENCY POWER RANGE HARVESTING CIRCUIT

The technology described herein is directed towards a reconfigurable intelligent surface (RIS) that harvests RF energy from incoming signals. In one implementation, there are two types of RIS elements (unit cells), one type engineered to capture and wirelessly harvest energy from incoming electromagnetic waves, while the other type redirects the incoming signals towards a predetermined direction. The harvested energy is combined and converted to DC power using a harvesting circuit. In one implementation, a dual-mode energy harvesting circuit employs a higher power rectifier sub-circuit and a lower power rectifier subcircuit, with a multiport circulator and switch that self-actuates to use one or the other rectifier subcircuit based on the combined RF input power captured by the energy harvesting elements. A multiple battery approach is described, in which one battery is charging based on the converted DC power, another, previously-charged battery is powering the reconfigurable intelligent surface components.