The impact of electromagnetic radiation created by micro base stations of 4G/5G cellular networks on receivers of medical short-range devices of different systems (capsule endoscopy system, body area network system, and active implant system) located inside buildings is analyzed for urban area. The analysis is made by the use of computer simulation involving the multipath radiowave propagation model which takes into account outdoor-to-indoor propagation. To perform the simulation, a 3D model of a fragment of urban area containing buildings of a height from 6 m to 60 m is developed. The integrated interference margin is used as a criterion of electromagnetic compatibility. Results of the analysis show that 4G/5G base stations can create the interference to all considered types of medical short-range devices in cases when emitters are located outside buildings and receptors are located inside buildings. In order to achieve electromagnetic compatibility between these base stations and considered medical systems, recommendations on reducing of levels of electromagnetic interference are given. Results of this research can be used to ensure safe operation of 4G/5G base stations with respect to vital medical devices.

A wideband worst case model to account for the diffraction of a plane electromagnetic (EM) wave by a system hull made of a conductive material is developed. The model can be used for estimating the amplitudes of electric and magnetic fields in places of antenna mounting on the hull of an airborne vehicle (aircraft, helicopter, etc.). The model is based on consideration of the fields radiated by electric dipole in a lowfrequency range and on the Fresnel approach to analysis of the diffraction in resonance-and high-frequency ranges. The use of analytical methods provides the high computational efficiency of the model. The developed model is validated by comparison of calculation results obtained by the model with results of numerical simulation performed in framework of FDTD and MOM (the ratio of the wavelength to the obstacle dimension is varied from 100 to 0.5).

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A new approach to the description of the resonance properties of objects (vehicle compartments, cases of electronic equipment, connecting cables, etc.) in the problems of the analysis of electromagnetic compatibility and electromagnetic protection is proposed. The essence of the approach is to create worst-case adaptive models that adjust (adapt) a priori unknown resonance frequencies of the simulated objects for each input stimulus in such a way as to provide the worst value of the criterion of electromagnetic compatibility (or protection criterion). Within the framework of the proposed approach, a worst-case adaptive model of the penetration of electric and magnetic fields into a shielding enclosure (e.g., into a vehicle compartment) is developed; the model is based on the existing non-adaptive model using analytical expressions for the field inside a rectangular waveguide. The developed model is validated by the following example: the impact of external electromagnetic pulses (the radar pulse and E1 HEMP) on a vehicle (jeep) is analyzed; the results of the calculation by the developed model are compared with the results of the FDTD calculation.