Peak SAR reduction in human head for handset applications with resistive sheets (R-cards)

Design Analysis of Ferrite Sheet Attachment for Sar Reduction in Human Head

“…The relative permittivity and conductivity of individual components were set to comply with industrial standards. In addition, definitions in [21][22][23] were adopted for material parameters involved in the SAM phantom head. In order to accurately characterize the performance over broad frequency range, dispersive models for all the dielectrics were adopted during the simulation [21].…”

“…A reduction over 13% for the spatial peak SAR over 1 gm averaging was achieved. Study on the effects of attaching ferrite sheet for SAR reduction was presented [16,21] and it was concluded that the position of shielding played an important role in the reduction effectiveness.…”

Shielding Effectiveness of Some Conductive Textiles and Their Capability to Reduce the Mobile Phones Radiation

“…Authors of [4] studied in 2008 the effect of nickel-zinc spinel ferrite shields of various shapes and sizes and concluded that a reduction factor of SAR of a maximum 52% could be obtained. In 2010 the use of resistive sheets was proposed for shielding [5], while both numerically and experimentally was demonstrated that a peak SAR reduction of over 60% was possible. Later on, the same year, a retrospective about the subject of shielding used for mobile phone radiation attenuation was also published [6].…”

A New Design of Metamaterials for SAR Reduction

“…It was found that the ferrite attachment reduces the SAR values due to the suppression of currents flowing on the front side of the cellular handset. Resistive cards (R-cards) sheet has also been discussed as a way to decrease the SAR values by reducing the radiation toward the human head [20].…”