Compact antenna integrated with a Greinacher voltage multiplier for ambient energy harvesting applications

Abstract

Radio frequency (RF) energy harvesting from freely available electromagnetic fields is a promising alternative for powering smart electronic devices. This article presents a compact and efficient rectenna for RF energy harvesting at an Industrial, Scientific, and Medical (ISM) band of 2.4 GHz. A compact microstrip antenna with opened-end slots and a full ground plane is designed. Moreover, a Greinacher voltage doubler topology-based rectifier was designed to sense small input power levels. The antenna and rectifier optimization were performed through the simulation software. The optimized prototypes were fabricated and measured individually and as well as an integrated system. Measured results were in good correlation with the simulations. A peak measured efficiency of 75% with a constant output voltage of 2.9 V was achieved for the proposed rectifier at a small input power of 10 dBm. Furthermore, for demonstration of the RF conversion efficiency and output voltage, the antenna was integrated with the rectifier of load resistance, which was later replaced by LED for WPT demonstration purposes. The demonstration verified that the proposed rectenna with achieved efficiency and sufficient output voltage is a promising candidate for powering smart electronic devices.