Design and development of optically transparent rectenna for RF energy harvesting applications

Abstract

An optically transparent ultra-wideband (UWB) Vivaldi antenna with a rectifier circuit is proposed in this paper. The proposed antenna is designed and fabricated on a soda-lime glass substrate with fluorine doped conductive oxide (FTO) as the conductive layer. A radial stub is used for better impedance matching and enhancing the impedance bandwidth of the antenna. It operates over a frequency range of 2–6 GHz with a bandwidth of 4 GHz. It has a directional radiation pattern with a realized peak gain of 2.5 dBi at 4 GHz and simulated radiation efficiency greater than 28%. The transparent antenna is integrated with a rectifier and a matching circuit for radio frequency energy harvesting applications. The rectifier and matching circuit is designed on an FR4 substrate. The fabricated rectenna provided a dc voltage of 140 mV from the ambient environment. The proposed rectenna can be installed in handheld devices that increase the scope of applications in automobiles and mobile communications.