Folded wire antenna with low SAR

In this study, a folded wire antenna for mobile phone handset has been developed for low specific absorption rate. The proposed antenna has a simple structure of comprising two open loops. Dual-band operation is achieved via a small printed area of 60 × 10 mm² isolating from the system circuit board of the mobile phone. A comparative study with a conventional printed invert-F antenna, which is frequently used as a handset antenna, has been carried out to demonstrate the interaction between antenna and human body. The experimental results indicate that the design has reductions of 82.3% of SAR value compared to the conventional printed invert-F antenna. These characteristics are partially owing to the balance structure of loop, and partially owing to the quasi-closed radiating elements. These mechanisms induce much less surface current distributions on the printed wire board of handset. This characteristic results in reduced hand-effect on antenna performances and degraded near-field radiated from the edges of printed wire board and radiation element.