Discrepancies of Measured SAR between Traditional and Fast Measuring Systems
- Why do discrepancies appear for the estimation of SAR by different fast measuring systems?
- Can we say fast measuring systems generate biased estimations if they differ appreciably from the traditional SAR measuring system?
- Which of the traditional measuring system and the fast measuring system is the more accurate?
2. Traditional SAR Measuring System
- Area scan: measure fields according to a two-dimensional coarse grid, the distance of which to the phantom surface is fixed, to locate the local maxima of the amplitude of electric fields.
- Zoom scan: a three-dimensional scanning within cubes centered at the location of local maxima, the grid step being smaller than that in the area scan.
- Interpolation and extrapolation: linear interpolation and cubic spline interpolation (and extrapolation) are used as necessary to deduce the amplitude at the points in a finer grid.
- Peak spatial-average SAR: obtained by performing numerically the integration in (1) based on the interpolated and extrapolated amplitude.
3. Fast SAR Measuring System Based on Field Reconstruction
3.1. Plane-Wave Expansion (PWE)
3.2. Field Reconstruction Making Use of More High-Frequency Components
4. Numerical Results
4.2. Verification of Post-Processing Procedures
4.3. Problem in Field Reconstructions
4.4. Uncertainty of Factors
4.5. Comparison between the Traditional and Fast Measuring Systems
Conflicts of Interest
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|Area scan||maximum grid spacing||20 mm if 3 GHz and mm otherwise|
|maximum distance between probe and surface of phantom||5 mm if 3 GHz and mm otherwise|
|Zoom scan||horizontal grid spacing||mm|
|minimum scan size||if 3 GHz and otherwise|
|maximum distance between probe and surface of phantom||5 mm if 3 Ghz and mm otherwise|
|(mm)||Cartesian coordinates of the probe position||, a being x, y, or z|
|c (dB)||coupling coefficient|
|amplitude of electric field|
|(radian)||phase angle of electric field|
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Liu, Z.; Allal, D.; Cox, M.; Wiart, J. Discrepancies of Measured SAR between Traditional and Fast Measuring Systems. Int. J. Environ. Res. Public Health 2020, 17, 2111. https://doi.org/10.3390/ijerph17062111
Liu Z, Allal D, Cox M, Wiart J. Discrepancies of Measured SAR between Traditional and Fast Measuring Systems. International Journal of Environmental Research and Public Health. 2020; 17(6):2111. https://doi.org/10.3390/ijerph17062111Chicago/Turabian Style
Liu, Zicheng, Djamel Allal, Maurice Cox, and Joe Wiart. 2020. "Discrepancies of Measured SAR between Traditional and Fast Measuring Systems" International Journal of Environmental Research and Public Health 17, no. 6: 2111. https://doi.org/10.3390/ijerph17062111