Institutional Repository On the e ects of straight metallic jewellery on the speci c absorption rates resulting from face illuminating radio communications devices at popular cellular frequencies

This paper presents simulated and measured phantom results for the possible effects that head worn jewellery may have on the relative levels of energy absorbed in the human head with cellular enabled mobile communications devices. FDTD electromagnetic code used with simple and complex anatomical mathematical phantoms were used to consider the interactions of metallic jewellery, heads, and representative sources at 900 and 1800MHz. Illuminated metallic pins of different lengths were positioned in front of the face. Initially, a homogenous phantom was used to understand the relative enhancement mechanisms. This geometry allowed the results to be validated with the industry standard DASY4 robot SAR measurement system related to the CENELEC head. Jewellery pins were then added to an anatomically realistic head. The relative increase in the 1g and 10g SAR, due to a pin with length 0.4 λ near the eyebrows of a complex, anatomically realistic head was approximately 3 times at 1800MHz. Such pins increased the SAR averaged over a 1g or 10g mass by redistributing the energy absorbed inside the head and focusing this energy towards the area of the head nearest the centre of the pin. Although, the pins increased the SAR, the SAR standards were not breached and the jewellery produced lower values than those of previous studies when the source was positioned close to the ear.

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