A High-FBR and Low-SAR Patch Antenna

In this paper, a microstrip patch antenna with a high front-to-back ratio (FBR) and low specific absorption rate (SAR) is proposed and studied. The antenna consists of a printed circular patch above a square ground plane, a coupled branch (CB) with hybrid loading, and a resistance-loaded ground slot (RLGS). By employing hybrid loading technique, additional magnetic currents are excited on the ground plane to cancel out the backward radiation from the original patch. The achieved FBR of the antenna exceeds 39.3 dB, effectively suppressing the SAR under wearable conditions.