A High Gain Dual Band Rectenna for RF Energy Harvesting Applications

In this article, a high gain dual band rectenna is proposed for energy harvesting applications. A dual band antenna is designed and optimized to operate at 3.5GHz and 5.8GHz frequency bands. The antenna is based on a multilayer substrate structure excited by aperture-coupling feed. In order to achieve a maximum gain of the antenna in both bands, a rectangular cell optimized by genetic algorithms is etched on the radiating element (patch). This antenna was simulated and fabricated, and the results show a good agreement in both bands (3.5 and 5.8 GHz) with a high gain of 10.2 dBi and 8.92 dBi for the first and second bands, respectively. A dual-band rectifier is also designed and studied to harvest the radio frequency energy absorbed by the antenna to DC energy at these frequency bands (3.5 GHz and 5.8GHz). This rectifier shows a good performance in terms of conversion efficiency which achieves 44% in the first band and 29% in the second band. As a result, an output voltage of 656.88mV for a low input power of 0 dBm is observed when the rectifier operates at both bands.