An autonomous wireless sensor node using a solar cell antenna for solar energy harvesting

An autonomous 3-5 GHz UWB sensor transmitter node uses a single solar cell of 2 × 2 cm
²
, sufficient to generate energy up to 20 mW of peak power outdoors, and acting as a broadband monopole antenna in the 3-10 GHz range, thus miniaturizing the overall system package. The sensor node consumes 10 μA average current when transmitting data bursts every 8.5 s at 1 kbits/s using OOK modulation. The harvested solar energy is stored in a supercapacitor to ensure continuity of transmission.