Ivana Raičević

The paper presents an analysis of the results of high-frequency electromagnetic field measurements performed in the living environment near base stations located at multiple sites. Measurement locations were selected based on the position of the antenna mast, at points where the highest levels of electromagnetic fields were expected. In addition to the results obtained by broadband measurements, which provide the value of total electromagnetic field within a specific frequency range, the paper also presents the results obtained by frequency-selective measurements. This type of measurement enables a more detailed analysis of individual electromagnetic field sources, i.e., identification of the contribution of individual mobile telephony systems to the overall electromagnetic field level across different frequency bands. The paper shows the maximum electric field values obtained by extrapolation, which could occur under conditions of maximum telecommunication traffic. This approach allows comparison of the measured values with the expected maximum values, thereby contributing to an objective assessment of exposure. Special attention in the paper is given to the analysis of the influence of various factors that can significantly affect the distribution and intensity of the electromagnetic field in the vicinity of base stations. Primarily, the impact of the height difference between the base station and the ground, as well as the distance of the base station from surrounding buildings and areas where people spend time, was considered. These parameters play an important role in determining electric field levels at specific locations, since changes in antenna mounting height, antenna tilt, or distance from the measurement point can significantly alter the distribution of electromagnetic field. Analysis of these factors makes it possible to better understand the propagation of electromagnetic waves and their interaction with the environment, as well as to assess the potential impact on the general public. The main objective of the conducted analysis is to determine the level of exposure of the general public to high-frequency electric fields in buildings where people spend extended periods of time. The results obtained in increased sensitivity areas were used to evaluate compliance with the limit values defined by the Regulation on Limits of Exposure to Electromagnetic Fields. In order to prevent excessive exposure of the general public to high-frequency electromagnetic field emitted by mobile telephony base stations, certain measures are implemented from the design and construction phase through the commissioning phase and continuously during operation. Regular measurements of electromagnetic field levels at defined intervals is a legal obligation of the owner of the electromagnetic field source. The paper provides recommendations and measures that are based on and confirmed by practical examples. Measures to reduce exposure primarily include proper selection of base station locations, correct antenna orientation, determination of safety zones with restricted access, as well as regular and proper maintenance of the installed equipment.

Keywords: electromagnetic field, electric field, exposure of the general public, rulebook, mobile telephony base station