Near Field Radio-Frequency Electromagnetic Field Exposure of a Western Honey Bee

It has been suggested that the wireless network evolution to smaller carrier wavelengths (from 2G to 5G) increases radio-frequency electromagnetic field (RF-EMF) absorption in Western Honey Bees (\emph{Apis mellifera}). It is unknown whether the radiation performance of antennas is stable when an insect appears in their vicinity. In this research, the absorbed power in a worker honey bee and the influence of the bee's presence on antennas' radiation performance is investigated for the newly used frequencies in 5G networks, from 6-240 GHz. To these aims, numerical simulations using the finite-difference time-domain method were performed, in which a bee model, obtained by micro-CT scanning, was employed. These simulations showed that in the near field, the absorbed power can increase by a factor of 53, from 6-240 GHz. This is a factor of 7 higher than the increase reported in the far field, in previous studies. Furthermore, the simulations revealed that antennas' radiation efficiency can decrease by up to -40 \% when a bee appears in the near field. Likewise, it was found that the gain pattern depends on the separation distance between the bee and the antenna, with a stronger dependency for higher frequencies.