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The wireless network evolution to smaller carrier wavelengths from (2G to 5G) could increase the RF-EMF absorption in insects. Near field RF-EMF exposure of insects to antennas’ radiation has only been studied near a single antenna element. However, nearly all realistic base station antennas are multi-element arrays. In this research, we show using FDTD that at a separation distance of 10 cm from a dipole, the RF-EMF absorbed power (Pabs), in the range of 6-120 GHz in a western honey bee, maximizes at 12 GHz. Moreover, our results show that when irradiated by a phased array operating at 60 GHz, Pabs maximizes in the separation distance range of 0.1-2 cm, at which ¼ of the input power into the array can be absorbed by the honey bee.

PurposeTo determine exposure to gradient switching fields of adults and children in a magnetic resonance imaging (MRI) scanner by evaluating internal electric fields within realistic models of adult male, adult female, and child inside transverse and longitudinal gradient coils, and to compare these results with compliance guidelines. Materials and MethodsPatients inside x-, y-, and z-gradient coils were simulated using anatomically realistic models of adult male, adult female, and child. The induced electric fields were computed for 1 kHz sinusoidal current with a magnitude of 1 A in the gradient coils. Rheobase electric fields were then calculated and compared to the International Commission on Non-Ionizing Radiation Protection (ICNIRP) 2004 and International Electrotechnical Commission (IEC) 2010 guidelines. The effect of the human body, coil type, and skin conductivity on the induced electric field was also investigated. ResultsThe internal electric fields are within the first level controlled operating mode of the guidelines and range from 2.7V m(-1) to 4.5V m(-1), except for the adult male inside the y-gradient coil (induced field reaches 5.4V m(-1)).The induced electric field is sensitive to the coil type (electric field in the skin of adult male: 4V m(-1), 4.6V m(-1), and 3.8V m(-1) for x-, y-, and z-gradient coils, respectively), the human body model (electric field in the skin inside y-gradient coil: 4.6V m(-1), 4.2V m(-1), and 3V m(-1) for adult male, adult female, and child, respectively), and the skin conductivity (electric field 2.35-4.29% higher for 0.1S m(-1) skin conductivity compared to 0.2S m(-1)). ConclusionThe y-gradient coil induced the largest fields in the patients. The highest levels of internal electric fields occurred for the adult male model. J. Magn. Reson. Imaging 2016;44:1360-1367.

This paper presents a new metric to evaluate electromagnetic exposure induced by wireless cellular networks. This metric takes into account the exposure induced by base station antennas as well as exposure induced by wireless devices to evaluate average global exposure of the population in a specific geographical area. The paper first explains the concept and gives the formulation of the Exposure Index (EI). Then, the EI computation is illustrated through simple phone call scenarios (indoor office, in train) and a complete macro urban data long-term evolution scenario showing how, based on simulations, radio-planning predictions, realistic population statistics, user traffic data, and specific absorption rate calculations can be combined to assess the index.

For the first time, the contribution of radio-frequent radiation originating from other people's devices to total own whole-body absorption is assessed in a simulation study. Absorption in a train environment due to base station's downlink is compared with absorption due to uplink (UL) of the user's own mobile device and absorption due to the UL of 0, 1, 5, or 15 other nearby active users. In a Global System for Mobile Communications (GSM) macro cell connection scenario, UL of 15 other users can cause up to 19% of total absorption when calling yourself and up to 100% when not calling yourself. In a Universal Mobile Telecommunications System (UMTS) femtocell connection scenario, UL of 15 other users contributes to total absorption of a non-calling user for no more than 1.5%. For five other users in the train besides the considered person, median total whole-body Specific Absorption Rate is reduced by a factor of about 400000 when deploying a UMTS femtocell base station instead of relying on the GSM macrocell