Low-SAR Back Cover Mobile Antenna

A novel antenna design with a low specific absorption rate (SAR) is introduced. The antenna has a very low profile and it is designed to be placed on the back cover of a mobile device at around 2 GHz. The solution is based on nested loops which distribute the field over a large volume so that the maximum SAR value remains relatively low in the user’s tissue. The proposed design also provides relatively good efficiency, considering the extremely low profile, and the close proximity of lossy human tissue and the phone’s main body. The manufactured prototype exhibits almost 50% lower maximum SAR than a patch antenna used as a reference.