SAR reduction of multi-band antenna by using Partially Reflective Surfaces

This paper describes the performance of a multi-band antenna with a Partially Reflective Surface (PRS) printed underneath the substrate to reduce the level of Specific Absorption Rate (SAR). The frequency band considered ranges from 850 MHz to 977 MHz and from 1.7 GHz to 2.1 GHz. The multi-band antenna placed above an FR4 substrate with the PRS printed below was found to reduce the 1-g average SAR in a specific anthropomorphic mannequin (SAM) model by 16.7-28.9 % as compared to the average SAR level of the no-PRS case, without unduly sacrificing antenna gain and radiation efficiency.