Characterization of Electromagnetic Properties of In Situ Soils for the Design of Landmine Detection Sensors: Application in Donbass, Ukraine

Round 1

Reviewer 1 Report

This paper describes different methods for determining electromagnetic parameters of soil near conflict regions in eastern Ukraine. The work represents an important and necessary contribution to future demining efforts in the region. The paper is well written and thoroughly researched in terms of background. There are a few minor editing and English points in the attached PDF.

Comments for author File: Comments.pdf

Author Response

Dear Reviewer 1,

Thank you for your helpful comments. We have fixed each of the problems you identified. Replies to all of your comments are in the PDF.

Author Response File: Author Response.pdf

Reviewer 2 Report

Despite under my point of view the paper is too long and should be much more concise, it is well written and easy to follow.

The idea of the authors seems to be to improve the performance of their GPR systems analyzing the soil properties of the area where they plan to use them in combination with other sensors.

Different sensors are used to estimate the classical EM parameters. Even if the conclusions regarding the impact on the GPR systems are not very significant, a meticulous surveying is carried out covering a wide area and I believe this study is of interest for other researchers working in the same or similar fields.

I am not native English speaker but according to my knowledge the paper is well written and reasoning can be follow easily

A couple of comments (or better suggestions)

* In the labels of Table I, the comma in Diameter and Length seems unnecessary
* In general the use ";" after Figure in the figure captions look a bit strange to me (but maybe it is the way it should be)
* Sometimes "," or "." is alternated in some figure captions to separate sentences, it would be clearer using only one of them.
* In figure 2: Line Numbers in black would be appreciated for clarity
* Table II instead of Make maybe Maker or Manufacturer?
* In several parts of the text "x-cm" or "x cm" is used, better unify criteria.
* In Table II reciever should be receiver
* In Table II I would change "Wenner array;10-cm A-Spacing" by "Wenner array 10 cm spacing" as the meaning of A seems to be "Array" (it is not clarified in the text)
* In line 122 the symbols of conductivity and permittivity do not look right in my version of the manuscript (the same symbol appears in both)
* In line 122 I would change "These are all frequency-dependent..." by " These parameters are all frequency-dependent" for clarity.
* Line 127 surficial by superficial
* Line 141-142 "read raw pulse travel times in nanosecons" what do you mind? "read raw pulse travel times of a few nanoseconds"?      
* Line 161 I would remove the spacing between paragraphs making only one for readability
* The beginning of paragraph in Line 179 says the same as the one in 155, probably better to unify it with 155 and start then Line 179 with the description of the complementary method for TDR using GPR
* The method proposed for the permittivity estimation with GPR is also a very well known method and, under my point of view, some references should be also provided. This method is routinely used in QA/QC road inspection since a long time. Saarenketo work may be a good reference for this.
* Again regarding this proposed method I miss also a comment about the accuracy of the method limited by the stability of the system. According to me, this is interesting for the reader. How often the calibration with a metal sheet should be done? Are the electronics stable enough to do a calibration at the begginning and work the whole day? Should one perform averaging to get more stable signal when doing this? How important is the short term amplitude jitter? I do not expect the authors answer all the questions but at least I think a general comment on that issue will be appreciated.
* Equations on the paper look with low quality like pasted images degrading work quality.
* Symbols related with equations should be revisited:
-- Line 198 "eR"
-- Line 194 "V" velocity better same as Line 415 also for consistency,
-- Line 193 "d" maybe better italic
-- Line 238 the meaning of "r" it is not explained. Maybe directly change by "range" as it is not used specifically in an equation.
-- In Table III velocity "v" looks not sharp and different than in the text, 302 "V" also better same as Line 415 for consistency, 
* The beginning of paragraph 228 repeats somehow again paragraph 205 and breaks the line of reasoning that has been followed. I would suggest to start directly with "At each measurement station... "         
* As bottom line the order of magnitude difference in results of permittivity from TDR and GPR is to me really surprising considering we are talking about 5cm gap (if I have understood the paper right).
*I miss also a mention to the impact of the research in some particularity related with holographic radars, this is one of the keywords of the paper but apart from the introduction there is no mention to that in the paper.

Author Response

Dear Reviewer 2,

Thank you for the detailed comments, and for spotting many small inconsistencies. You have a very keen eye.

Responses in the attached document.

Author Response File: Author Response.pdf