Fig. 6: Demonstration of energy harvesting of wireless radio frequency power.
a Schematic of the circuit used for the energy harvesting. The wireless signal from the horn antenna or microstrip patch-antenna with a power of 0 dBm is irradiated on the array of eight electrically connected STOs in series at zero magnetic field and dc bias. The rectified signal is stored in the capacitor, which is then supplied to the dc–dc boost converter for supplying the voltage to power the red LED. b Rectified response of eight oscillators in series when irradiated by a horn antenna fed by a signal generator with the gain of 6–7 dBi in the range of 1–4 GHz. c Rectified response of the eight STOs connected in series at rf power of 0 dBm from the patch antenna at zero magnetic field and dc bias. d Charging voltage (Vc) of the capacitor from the eight STOs rectified output with time on the left axis. The right axis shows the dc–dc converter output (Vout) when the wireless output is off. e The output voltage from the dc–dc boost converter in response to the power of 0 dBm (1 mW) applied from the signal generator to the patch antenna with on and off time of 5 and 30 s, respectively.
