A Review: Methods to Lower Specific Absorption Rate for Mobile Phones

This paper seeks a terse review of various methods implemented to acquire low SAR for mobile antennas. The techniques to be reviewed include-Reflectors, Metamaterials, Metal Strips, RF shields, Directive antennas and EBG. Each technique with the prospect of reducing SAR has some shortcomings because of which it is not a sustainable option, so it is not preferred for extensive use. The limitations include an imbalance between one or more parameters - satisfying the requirements of bandwidth, efficiency, gain, directivity. Seemingly, it has not been possible so far to achieve desired results for all these parameters together for new generation mobile phones. All parameters mentioned above appear to offer the least compromising results for PBG against the rest.