A Low-SAR Frame-Antenna for Mobile Phone Based on Tangential Fields Cancellation

A low specific absorption rate (SAR) frame antenna for smartphone is proposed based on the tangential fields cancellation. The proposed antenna contains a T-shaped feeding, a modified folded dipole and loaded inductors, which are used to cancel tangential electric field by introducing reverse current. The measured -6dB bandwidth of the proposed antenna is 335MHz from 3.3GHz-3.6GHz. The measured total efficiency ranges from 62% to 85%. The measured normalized maximum 10g peak spatial-average SAR is 1.09W/kg. The SARs in different reference planes also have similar magnitudes and distribution and can all be kept at a low level.