A survey on low power RF rectifiers efficiency for low cost energy harvesting applications

In this paper the analysis, simulation and prototyping of radio frequency rectifier topologies for ambient energy harvesting applications are evaluated, highlighting the effects of input power levels below −10 dBm. The equivalent diode impedance model is taken into consideration for better interpreting its effects when attached to each rectifier topology. Furthermore, the output capacitance modeling and its effects over the rectifier efficiency are discussed for different capacitance types, including a radial stub. A prototype of the most prominent topology was built on a low cost FR-4 substrate for RF harvesting in the range of −10 to −20 dBm, resulting in an approximate efficiency between 40% and 25%, respectively.