Flexible metallodielectric electromagnetic bandgap surfaces for improved handset antenna performance

We investigate the use of miniaturised metallodielectric electromagnetic bandgap (MEBG) structures embedded in the case of a mobile handset as a means of decoupling the antenna from the user's hand. The closely coupled MEBG concept is employed to achieve miniaturisation of the order of 15:1. The performance of a prototype handset with an embedded conformal MEBG is assessed experimentally and compared to a similar prototype without the MEBG. Reduction in the de-tuning of the antenna due to the human hand by virtue of the MEBG is demonstrated. Moreover the efficiency of the handset when loaded with a human hand model is shown to improve when the MEBG is in place. The improvements are attributed to the de-coupling of the antenna from the user's hand, which is achieved by means of suppressing the fields in the locality of the hand.