Low SAR Phased Antenna Array for Mobile Handsets
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Low SAR Phased Antenna Array for Mobile HandsetsAbstract
A two-element phased antenna array for a mobile handset is investigated using the Finite Difference Time Domain (FDTD) method. The array is designed to provide a spatial minimum in SAR in the near field zone inside the human head. The optimisation algorithms to obtain the minimum peak specific absorption rate (SAR) and minimum total absorbed power are addressed. It is found that these criteria are not seriously conflicting. The effects of the head-array spacing on the optimum array feeding voltages and the reduction in SAR are discussed. The results are compared with those from a normal single element handset, showing that the overall efficiency and azimuth coverage are improved and that peak specific absorption rate in the head can be reduced by at least 8 dB.
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