A Compact 5.8 GHz Rectenna With High Conversion Efficiency Enabled by the Harmonic Suppression for Wireless Power Transfer

A 5.8 GHz compact rectenna based on the wide-slot antenna with harmonic suppression is proposed. The wide-slot antenna has the advantages of wide impedance bandwidth, easy integration, and simple structure which can not only ensure the overall performance of the rectenna but also promotes the commercialization of wireless power transmission. To reduce the profile, the rectifier circuit was integrated on the backside of the wide-slot antenna with a matching network and a dc-pass filter. Further, to improve the conversion efficiency of the rectenna, two microstrip stubs on the feed line of the antenna were introduced for harmonic suppression. Finally, the impedance bandwidth of 33% with a peak gain of 6.6 dBi over the wide band of 4.63-6.51 GHz is achieved and the maximum conversion efficiency of 65.0% and an output dc voltage of 6.20 V have also been obtained with a 910 Ω load at the input power of 18 dBm.