A mobile phone PCS PIFA with low SAR

In this paper, the effect of short pin position on the radiation characteristics of a PCS band PIFA above a finite ground is analyzed using Ansoft HFSS. The analysis showed that the impedance bandwidth varied with different ground pin positions. The change in antenna bandwidth and other radiation characteristics was due to the change in the coupling mechanism between the PIFA mode and the ground plane mode in a way similar to changing the ground plane size. It is found that PIFAs with different radiator lengths can be tuned to the PCS band by proper selection of the short pin position. The analysis results can also be used to avoid designs with unnecessarily wide bandwidths, which are probably associated with higher SAR and lower efficiency. Two different PCS band PIFAs with similar bandwidths were fabricated and tested with an operational phone.