In Situ Assessment of 5G NR Massive MIMO Base Station Exposure in a Commercial Network in Bern, Switzerland

Round 1

Reviewer 1 Report

The paper presents a methodology and apparatus to measure RF exposure to 5G NR signals (3.6GHz). It is very well written with an excellent scientific methodology. The results are correct and properly explained with an excellent background in terms of theory (equations, EM field ...). This paper will contribute significantly to inform public on a trustworthy study of 5G exposure.

Author Response

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Reviewer 2 Report

This paper describes the assessment of the range of actual and maximum radiofrequency electromagnetic field exposure levels in a 5G NR commercial network. It is a well written and technically sound study based on the measurement methodology described in reference 13.

The authors should clarify the following points:

In lines 124-127 it is mentioned that these measurements were performed using a Narda SRM-3006 field strength analyzer simultaneously, at other positions than the FSV measurements. The authors should mention how these positions relate to the positions of the FSV measurements.

The authors should also state the technical characteristics of the probe used with the SRM unit.

The expanded measurement uncertainty of the SRM setup and the used measurement settings for obtaining the results of Table 1 should be mentioned.

The authors should comment on the validity of the comparisons made in the paper between the acquired results in Table 1 for the 3500 MHz band with the SRM unit and the results of the FSV measurements, taking into account the different equipment used and the different positions where the measurements took place.

Author Response

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Reviewer 3 Report

Aerts et al In-Situ assessment…

I only have some minor editorial comments.

Already in the abstract I reacted to extrapolated values of the electric field given with three figure accuracy. The measurement of these kind of fields is done with at least ±3 dB error and on top of that extrapolated means that it is enough with only one figure to give this estimate (line 11).

I object to the wording in line 22-24 that WHO concluded no adverse effect, and this was referenced to 2010. But in 2011 IARC classified RF as a class IIB, published in 2012. I suggest to delete these lines since they do not contribute to the text.

On line 32 a ref is given to ICNIPR 1998, why not refer to the new ICNIRP from 2020. This old ref is coming back on line 264 and since the new ICNIRP has been out from 2020 it does this paper look a bit old, probably written some time ago. Please, update! The new ICNIRP does not give specific E field values but rather power density, could this be addressed here?

In the keywords there are now some that are already in the title (5G, Massive MIMO) and they should be replaced.

Line 92. It is not clear over what time the time-average was done. Order of seconds or more? On line 193 30 s is given. What about averaging over the 6-min time frame?

In the final discussion it would have been of interest to get some lines about occupational exposure close to the base station antennas with the 5G signals.

 

 

Author Response

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