Rectennas For Wireless Energy Harvesting And Wireless Power Transfer Applications

Rectenna obtains electromagnetic energy from free space and converts it into useful DC power.It can be used in both low-power wireless energy harvesting(WEH)and high-power wireless energy transmission(WPT).The thesis focuses on rectenna working in ISM(Industrial,Scientific,and Medical)frequency band,which has engineering and academic value.The main work of this paper is as follows:1.For WEH and WPT applications,a compact microstrip antenna with open groove and full ground plane is designed,and a rectifier based on Greincher voltage doubling topology is designed.By combining the designed antenna and rectifier,the design for a compact and efficient rectenna operating at 2.4 GHz is optimized and finished.2.The optimized 2.4 GHz rectifier was fabricated.The measurements for individual components and system were carried out.The measured results were in good agreement with the simulation results.The experimental results show that the proposed rectenna has high efficiency and sufficient output voltage.When the output voltage is 2.9V,the peak measurement efficiency of the rectifier is 75%under 10dBm input power.3.A dual-frequency compact rectenna for 2.4 GHz and 5.58 GHz is proposed.The dual-frequency matching is realized by using two-stage T-type network.The proposed design has good simulation results with advantages in power conversion and output voltage.A prototype was fabricated and measurement results were quite near to Simulation results.At 2.45 GHz and 5.8 GHz frequencies 2.8 V and 2 V with 67%and 61%efficiency respectively obtained at 5 dBm input power.