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Characterization and Evaluation of a Commercial WLAN System for Human Provocation Studies.

Zentai N, Fiocchi S, Parazzini M, Trunk A, Juhász P, Ravazzani P, Hernádi I, Thuróczy G - Biomed Res Int (2015)

Bottom Line: Finally, the specific absorption rate (SAR) generated by the CU was estimated computationally in the head of two human models.Results suggest that exposure to RF fields of WLAN systems strongly depends on the sets of the router configuration: the stability of the exposure was more constant and reliable when both antennas were active and vertically positioned, with best signal quality obtained with the R52n router board at channel 9, in UDP mode.The maximum levels of peak SAR were far away from the limits of international guidelines with peak levels found over the skin.

View Article: PubMed Central - PubMed

Affiliation: Department of Experimental Neurobiology, University of Pécs, 6 Ifjúság Útca, Pécs 7624, Hungary.

ABSTRACT
This work evaluates the complex exposure characteristics of Wireless Local Area Network (WLAN) technology and describes the design of a WLAN exposure system built using commercially available modular parts for the study of possible biological health effects due to WLAN exposure in a controlled environment. The system consisted of an access point and a client unit (CU) with router board cards types R52 and R52n with 18 dBm and 25 dBm peak power, respectively. Free space radiofrequency field (RF) measurements were performed with a field meter at a distance of 40 cm from the CU in order to evaluate the RF exposure at several signal configurations of the exposure system. Finally, the specific absorption rate (SAR) generated by the CU was estimated computationally in the head of two human models. Results suggest that exposure to RF fields of WLAN systems strongly depends on the sets of the router configuration: the stability of the exposure was more constant and reliable when both antennas were active and vertically positioned, with best signal quality obtained with the R52n router board at channel 9, in UDP mode. The maximum levels of peak SAR were far away from the limits of international guidelines with peak levels found over the skin.

No MeSH data available.


Related in: MedlinePlus

SAR10 g distributions over (a) grey matter and (b) white matter of “Ella” (1st row) and “Duke” (2nd row). Scaling bar is normalized to the peak SAR10 g found over each model (i.e., 22.77 mW/kg and 10.37 mW/kg for Ella and Duke, resp.). White squares indicate the maxima peak SAR10 g locations.
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fig12: SAR10 g distributions over (a) grey matter and (b) white matter of “Ella” (1st row) and “Duke” (2nd row). Scaling bar is normalized to the peak SAR10 g found over each model (i.e., 22.77 mW/kg and 10.37 mW/kg for Ella and Duke, resp.). White squares indicate the maxima peak SAR10 g locations.

Mentions: Figure 12 shows an example of exposure assessment performed by computational electromagnetics on the heads of the two human models, considering as source the CU being fed at 20 dBm (100 mW and 100% duty cycle) at 2.45 GHz and a distance between head and CU antennas of 40 cm, tailored for an experimental study on human volunteers. In light of some contrasting results found by studies on the effects of acute RF-EMF exposure and specifically those of Wi-Fi exposure on higher-order cognitive functions as well as on brain physiology (see, e.g., [36–45]), we believe that it would be interesting to assess the power absorption in specific brain structures involved in performance in cognitive tasks. The target tissues for exposure were assumed to be the forehead skin and the underlying brain tissue such as the cortex (grey matter) and axonal pathways (forebrain white matter). White squares in the figure indicate the maxima peak SAR10 g locations. The results refer to the sitting positions: however, given the same head-CU distances taken for the two simulated positions, they are almost equivalent (differences below 5%).


Characterization and Evaluation of a Commercial WLAN System for Human Provocation Studies.

Zentai N, Fiocchi S, Parazzini M, Trunk A, Juhász P, Ravazzani P, Hernádi I, Thuróczy G - Biomed Res Int (2015)

SAR10 g distributions over (a) grey matter and (b) white matter of “Ella” (1st row) and “Duke” (2nd row). Scaling bar is normalized to the peak SAR10 g found over each model (i.e., 22.77 mW/kg and 10.37 mW/kg for Ella and Duke, resp.). White squares indicate the maxima peak SAR10 g locations.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4477099&req=5

fig12: SAR10 g distributions over (a) grey matter and (b) white matter of “Ella” (1st row) and “Duke” (2nd row). Scaling bar is normalized to the peak SAR10 g found over each model (i.e., 22.77 mW/kg and 10.37 mW/kg for Ella and Duke, resp.). White squares indicate the maxima peak SAR10 g locations.
Mentions: Figure 12 shows an example of exposure assessment performed by computational electromagnetics on the heads of the two human models, considering as source the CU being fed at 20 dBm (100 mW and 100% duty cycle) at 2.45 GHz and a distance between head and CU antennas of 40 cm, tailored for an experimental study on human volunteers. In light of some contrasting results found by studies on the effects of acute RF-EMF exposure and specifically those of Wi-Fi exposure on higher-order cognitive functions as well as on brain physiology (see, e.g., [36–45]), we believe that it would be interesting to assess the power absorption in specific brain structures involved in performance in cognitive tasks. The target tissues for exposure were assumed to be the forehead skin and the underlying brain tissue such as the cortex (grey matter) and axonal pathways (forebrain white matter). White squares in the figure indicate the maxima peak SAR10 g locations. The results refer to the sitting positions: however, given the same head-CU distances taken for the two simulated positions, they are almost equivalent (differences below 5%).

Bottom Line: Finally, the specific absorption rate (SAR) generated by the CU was estimated computationally in the head of two human models.Results suggest that exposure to RF fields of WLAN systems strongly depends on the sets of the router configuration: the stability of the exposure was more constant and reliable when both antennas were active and vertically positioned, with best signal quality obtained with the R52n router board at channel 9, in UDP mode.The maximum levels of peak SAR were far away from the limits of international guidelines with peak levels found over the skin.

View Article: PubMed Central - PubMed

Affiliation: Department of Experimental Neurobiology, University of Pécs, 6 Ifjúság Útca, Pécs 7624, Hungary.

ABSTRACT
This work evaluates the complex exposure characteristics of Wireless Local Area Network (WLAN) technology and describes the design of a WLAN exposure system built using commercially available modular parts for the study of possible biological health effects due to WLAN exposure in a controlled environment. The system consisted of an access point and a client unit (CU) with router board cards types R52 and R52n with 18 dBm and 25 dBm peak power, respectively. Free space radiofrequency field (RF) measurements were performed with a field meter at a distance of 40 cm from the CU in order to evaluate the RF exposure at several signal configurations of the exposure system. Finally, the specific absorption rate (SAR) generated by the CU was estimated computationally in the head of two human models. Results suggest that exposure to RF fields of WLAN systems strongly depends on the sets of the router configuration: the stability of the exposure was more constant and reliable when both antennas were active and vertically positioned, with best signal quality obtained with the R52n router board at channel 9, in UDP mode. The maximum levels of peak SAR were far away from the limits of international guidelines with peak levels found over the skin.

No MeSH data available.


Related in: MedlinePlus