Near‐field dosimetry for in vitro exposure of human cells at 60 GHz

Abstract

Due to the expected mass deployment of millimeter-wave wireless technologies, thresholds of potential millimeter-wave-induced biological and health effects should be carefully assessed. The main purpose of this study is to propose, optimize, and characterize a near-field exposure configuration allowing illumination of cells in vitro at 60 GHz with power densities up to several tens of mW/cm(2) . Positioning of a tissue culture plate containing cells has been optimized in the near-field of a standard horn antenna operating at 60 GHz. The optimal position corresponds to the maximal mean-to-peak specific absorption rate (SAR) ratio over the cell monolayer, allowing the achievement of power densities up to 50 mW/cm(2) at least. Three complementary parameters have been determined and analyzed for the exposed cells, namely the power density, SAR, and temperature dynamics. The incident power density and SAR have been computed using the finite-difference time-domain (FDTD) method. The temperature dynamics at different locations inside the culture medium are measured and analyzed for various power densities. Local SAR, determined based on the initial rate of temperature rise, is in a good agreement with the computed SAR (maximal difference of 5%). For the optimized exposure setup configuration, 73% of cells are located within the ±3 dB region with respect to the average SAR. It is shown that under the considered exposure conditions, the maximal power density, local SAR, and temperature increments equal 57 mW/cm(2) , 1.4 kW/kg, and 6 °C, respectively, for the radiated power of 425 mW.

Effects of 60-GHz millimeter waves on neurite outgrowth in PC12 cells using high-content screening

“…The anechoic exposure chamber is located in a temperaturecontrolled anechoic MEMMERT UNE400 incubator (Memmert GmbH, Schwabach, DE) covered inside by absorbing materials. The exposure levels were described in detail for a 6-well tissue culture plate [30]. However, since we used 96-well plates, the exposure conditions were therefore changed.…”

Advanced feed for a 60-GHz exposure chamber

“…To comply with these specifications, a number of exposure systems has been developed recently [1][2][3][4][5][6][7][8]. However, most of them are based on standard feeds (open waveguide and horn antennas) that suffer from the low exposure efficiency and insufficient uniformity of the power density distribution at the surface of the samples under test (SUT).…”

Personal Exposimeter for Radiation Assessment in Real Environments in the 60-GHz Band

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