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SAR versus Sinc: what is the appropriate RF exposure metric in the range 1-10 GHz? Part I: using planar body models

Journal Article


Abstract


  • This is the first of two papers addressing the most appropriate crossover frequency at which incident

    power flux density (Sinc) replaces the spatial peak value of the specific energy absorption rate (SAR)

    averaged over 1 or 10 g (i.e., peak 1 g or 10 g SAR) as the basic restriction for protecting against

    radiofrequency heating effects in the 1-10 GHz range. Our general approach has been to compare the

    degree of correlation between these basic restrictions and the peak induced tissue temperature rise

    (T) for a representative range of population/exposure scenarios. In this paper we particularly address

    the effect of human population diversity in the thickness of body tissue layers at eight different sites

    of the body. We used a Monte Carlo approach to specify 32,000 models (400 models for each of 8

    body sites for 10 frequencies) which were representative of tissue thicknesses for age (18-74 years)

    and sex at the eight body sites. Histogram distributions of Sinc and peak 1 g and 10 g SAR

    corresponding to a peak 1 °C temperature rise were obtained from RF and thermal analyses of 1D

    multiplanar models exposed to a normally incident plane wave ranging from 1-10 GHz in thermoneutral

    environmental conditions. Examination of the distribution spread of the histograms indicated

    that peak SAR was a better predictor of peak tissue temperature rise across the entire 1-10 GHz

    frequency range than Sinc, as indicated by the smaller spread in its histogram distributions, and that

    peak 10 g SAR was a slightly better predictor than peak 1 g SAR. However, this result must be

    weighed against partly conflicting indications from complex body modeling in the second paper of

    this series, which incorporates near-field effects and the influence of complex body geometries.

Authors


Publication Date


  • 2010

Citation


  • Anderson, V., Croft, R. J. & McIntosh, R. (2010). SAR versus Sinc: what is the appropriate RF exposure metric in the range 1-10 GHz? Part I: using planar body models. Bioelectromagnetics, 31 (6), 454-466.

Scopus Eid


  • 2-s2.0-77956911552

Ro Metadata Url


  • http://ro.uow.edu.au/hbspapers/2036

Has Global Citation Frequency


Number Of Pages


  • 12

Start Page


  • 454

End Page


  • 466

Volume


  • 31

Issue


  • 6

Abstract


  • This is the first of two papers addressing the most appropriate crossover frequency at which incident

    power flux density (Sinc) replaces the spatial peak value of the specific energy absorption rate (SAR)

    averaged over 1 or 10 g (i.e., peak 1 g or 10 g SAR) as the basic restriction for protecting against

    radiofrequency heating effects in the 1-10 GHz range. Our general approach has been to compare the

    degree of correlation between these basic restrictions and the peak induced tissue temperature rise

    (T) for a representative range of population/exposure scenarios. In this paper we particularly address

    the effect of human population diversity in the thickness of body tissue layers at eight different sites

    of the body. We used a Monte Carlo approach to specify 32,000 models (400 models for each of 8

    body sites for 10 frequencies) which were representative of tissue thicknesses for age (18-74 years)

    and sex at the eight body sites. Histogram distributions of Sinc and peak 1 g and 10 g SAR

    corresponding to a peak 1 °C temperature rise were obtained from RF and thermal analyses of 1D

    multiplanar models exposed to a normally incident plane wave ranging from 1-10 GHz in thermoneutral

    environmental conditions. Examination of the distribution spread of the histograms indicated

    that peak SAR was a better predictor of peak tissue temperature rise across the entire 1-10 GHz

    frequency range than Sinc, as indicated by the smaller spread in its histogram distributions, and that

    peak 10 g SAR was a slightly better predictor than peak 1 g SAR. However, this result must be

    weighed against partly conflicting indications from complex body modeling in the second paper of

    this series, which incorporates near-field effects and the influence of complex body geometries.

Authors


Publication Date


  • 2010

Citation


  • Anderson, V., Croft, R. J. & McIntosh, R. (2010). SAR versus Sinc: what is the appropriate RF exposure metric in the range 1-10 GHz? Part I: using planar body models. Bioelectromagnetics, 31 (6), 454-466.

Scopus Eid


  • 2-s2.0-77956911552

Ro Metadata Url


  • http://ro.uow.edu.au/hbspapers/2036

Has Global Citation Frequency


Number Of Pages


  • 12

Start Page


  • 454

End Page


  • 466

Volume


  • 31

Issue


  • 6