Green energy harvesting from ambient RF radiation

This paper presents the design of a rectifying antenna i.e. rectenna for energy harvesting application. A circularly polarized multiband microstrip antenna is used to collect the electromagnetic energy radiated from cell towers in the CDMA and GSM bands and schottky diodes are used to convert it into DC power. The experimental results for prototype antenna and rectifier structures are verified with the simulated results. The conversion efficiency of the rectenna system is evaluated as 23% at GSM 900 frequency band.