High efficient rectenna using a harmonic rejection low pass filter for RF based wireless power transmission

A high efficient 915 MHz rectenna is designed using a harmonic rejection low pass filter (LPF). The proposed rectenna consists of a slot coupled dipole antenna and high order harmonic rejection LPF, voltage doubler type rectifier, a LPF for the DC path, and resistive load. The use of a 2^nd and 3^rd harmonic rejection LPF in the rectenna results in high conversion efficiency. Performance of rectenna is analyzed using harmonic balance analysis. The proposed rectenna achieves a RF to DC conversion efficiency of 74.8 % when the received RF power is 62.2 mW. The maximum output DC voltage across R_L was 7.2 V at a distance of d = 50 cm from the transmitter and the possible maximum transmission distance can be achieved by 2 m at steel box girder type Gimpo Bridge.