A 2.45 GHz circular patch antenna with harmonic suppression for wireless power transmission

This paper proposed a new circular patch antenna design with harmonics suppression capability. The purpose of harmonic suppression antenna is to eliminate the use of harmonic filter circuit in rectenna circuit. By introducing slits at the antenna patch and stub at the transmission line, unwanted harmonics frequencies are successfully suppressed. In addition, the size of proposed circular patch antenna is reduced by using partial ground and circular slot technique at the ground plane. The patch antenna is design on FR4 substrate with ε_r=4.7 and a thickness of 1.6 mm has -48dB return loss at 2.45GHz and suppress the second and third harmonic up to -3dB. The proposed harmonic suppression antenna can be applied in rectenna and active integrated antenna (AIA) applications, thus the circuit become compact, cheaper and more efficient.