RF exposure of biological systems in radial waveguides

Two radial waveguide exposure systems for multiple biological targets are described that were conceived, dimensioned, implemented, measured and dosimetrically analyzed. In the first case, a number of 120 hamsters was exposed with mobile communication signals at 383 and 900 MHz. The variation of the dissipated energy within the animals could be reduced to less than 30% though the objects were not restrained. Whole body specific absorption rates of 80 mW/kg were applied. The other system was used for exposing hamster's pineal glands in culture. The small size of the samples yields an even smaller variation of the exposure of 2.4%. This is a consequence of the excellent uniformity of the electromagnetic field distribution across the exposure region, which was achieved by a good rotational symmetry of the waveguide and a careful design of the feed antenna and the absorber/shortcut combination. The paper reports on the technical aspects of the RF exposure.