A surrogate model to assess the whole body SAR induced by multiple plane waves at 2.4 GHz

  • Thierry Kientega
  • Emmanuelle Conil
  • Abdelhamid Hadjem
  • Elodie Richalot
  • Azzedine Gati
  • Man Fai Wong
  • Odile Picon
  • Joe Wiart
Article

Abstract

The assessment of the exposure to electromagnetic waves is nowadays a key question. Dealing with the relationship between exposure and incident field, most of previous investigations have been performed with a single plane wave. Realistic exposure in the far field can be modeled as multiple plane waves with random direction of arrival, random amplitude, and random phase. This paper, based on numerical investigations, studies the whole body specific absorption rate (SAR) linked to the exposure induced by five random plane waves having uniformly distributed angles of arrival in the horizontal plane, log-normal distributed amplitudes, and uniformly distributed phases. A first result shows that this random heterogeneous exposure generates maximal variations of ±25% for the whole body specific absorption. An important observation is that the exposure to a single plane wave arriving face to the body, used for the guidelines, does not constitute the worst case. We propose a surrogate model to assess the distribution of the whole body SAR in the case of an exposure to multiple plane waves. For a sample of 30 values of whole body SAR induced by five plane waves at 2.4 GHz, this simple approach, considering the resulting SAR as the sum of the SAR induced by each isolated plane wave, leads to an estimated distribution of whole body SAR following the real distribution with a p value of 76% according to the Kolmogorov statistical test.

Keywords

Radiofrequencies Surrogate model Specific Absorption Rate (SAR) FDTD Statistical tests Multiple plane waves exposure 

Notes

Acknowledgment

This work was sponsored by the Agence Nationale de la Recherche in the framework of the Mutlipass project (whist.institut-telecom.fr).

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Copyright information

© Institut Télécom and Springer-Verlag 2011

Authors and Affiliations

  • Thierry Kientega
    • 1
    • 2
  • Emmanuelle Conil
    • 1
    • 2
  • Abdelhamid Hadjem
    • 1
    • 2
  • Elodie Richalot
    • 3
  • Azzedine Gati
    • 1
    • 2
  • Man Fai Wong
    • 1
    • 2
  • Odile Picon
    • 3
  • Joe Wiart
    • 1
    • 2
  1. 1.France Telecom R&D, Issy-les-MoulineauxParisFrance
  2. 2.Whist common labs of Orange Labs and Institut Telecom-Paris TechParisFrance
  3. 3.ESYCOMUniversité Paris Est-Marne-la-ValléeParisFrance

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