Specific absorption rate and electric field measurements in the near field of six mobile phone base station antennas

Abstract

In this article, the exposure to radio frequency electromagnetic fields was studied in close proximity (distances of 10, 100, 300, and 600 mm) to six base station antennas. The specific absorption rate (SAR) in 800 mm x 500 mm x 200 mm box phantom as well as unperturbed electric field (E) in air was measured. The results were used to determine whether the measurement of local maximum of unperturbed electric field can be used as a compliance check for local exposure. Also, the conservativeness of this assessment method compared to the ICNIRP basic restriction was studied. Moreover, the assessment of whole-body exposure was discussed and the distance ranges presented in which the ICNIRP limit for local exposure could be exceeded before the limit for whole-body SAR. These results show that the electric field measurement alone can be used for easy compliance check for the local exposure at all distances and for all antenna types studied. However, in some cases when the local peak value of E was compared directly to the ICNIRP reference level for unperturbed E, the exposure was overestimated only very slightly (by factor 1.1) compared to the basic restriction for localized SAR in a human, and hence these results can not be generalized to all antenna types. Moreover, it was shown that the limit for localized exposure could be exceeded before the limit for the whole-body average SAR, if the distance to the antenna was less than 240 mm.

Effect of Radiation Emitted by Wireless Devices on Male Reproductive Hormones: A Systematic Review

“…Generally, a near-field is one wavelength (λ) or less away from the source of radiation, whereas a far-field is about two wavelengths (2λ) away from the antenna (Occupational Safety Health Administration, 1990). Toivonen et al (2019) demonstrated that the ICNIRP limit for localized exposure (2 W/kg) could be reached if the distance between the antenna and the body is <24 cm. As a consequence, when people hold their phones next to their heads or wear them on their bodies, they may be exposed to very intense near-field radiation from the device at close or touching distances.…”

Evaluation of the safety of users of active implantable medical devices (AIMD) in the working environment in terms of exposure to electromagnetic fields – practical approach to the requirements of European Directive 2013/35/EU

“…Consequently, in the vicinity of EMF sources, various hazards for implant users need to be identified and evaluated, especially for users of AIMD. In the systematic considerations, the EMF influence on AIMD functions may be split into the following groups (where it is not excluded that they will present together): -influence on the electric circuit of the AIMD, -influence on the internal memory of the AIMD, -influence on mechanical structures -by heating, reposition, etc., Pacing inhibition (complete or temporary stop of pacing); the implant interprets electrical potentials from EMF electrodynamic interaction as the proper heart rate and stops the pacing, even in the absence of the intrinsic heart rate EAS systems [5,6]; induction hobs (25-34 kHz) [7]; GSM [6,[8][9][10]; vicinity of BTS [11,12]; MD gates [13]; MRI scanners (1.5 T) [6,14]; ESU [6,15] CP [11,12]; 3.4. 400 kV power lines [19]; 3.5.…”

Analysis of the effect of mobile phone base station antenna loading on localized SAR and its consequences for measurements

“…Previous work in the area of base station SAR measurements have mainly focused on small base station products and antennas [Hamberg et al, 2003;Ilvonen et al, 2008]. Some results on SAR measurements for larger base station antennas are available [Cooper et al, 2002;Joseph and Martens, 2005;Gosselin et al, 2009;Toivonen et al, 2009], but these studies did not focus on the issues discussed in this article.…”