Energy harvesting circuit using integrated transformer

In this work we present a prototype circuit to harvest energy from radio frequency (RF) electromagnetic waves based on an integrated transformer together with a half-wave multi-stage rectifier. This circuit is designed to be impedance matched to a standard 50 Ω antenna and to operate at 2.4 GHz with input power as low as −15 dBm. The circuit presented here shows that it is possible to harvest low power input signals and therefore it can be used to supply alone a circuit, or to work as a backup battery charger. The circuit was designed and simulated in a standard 130 nm CMOS process.