Applications of Shielding Techniques to Enhance the Antenna Performance of Mobile Communications and Reduce SAR Induction in the Human Head

Applications of shielding techniques are proposed to enhance the antenna performance of mobile communications. The shielding structures for the base station antennas are based on an implementation of resistive plates that tend to reflect the antenna radiation in the side lobes to main beam region, and hence optimize the overlapping coverage between sectors. On the other hand, magnetic materials are employed to design the shielding structures for handset antennas in order to provide good shielding effectiveness for magnetic near fields that were shown to be the major cause of a specific absorption rate (SAR) in the human head. Our studies show that with this shielding application the antenna performance can be enhanced while simultaneously reducing the SAR induction.

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