Pre-Processing of Simulated Synthetic Aperture Radar Image Scenes Using Polarimetric Enhancement for Improved Ship Wake Detection
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsSee attached document.
Comments for author File: 
Comments.pdf
The english is good. But avoid using words like "obviously" or "tough" when describing results and performance. State values supported by your work or previous literatures.
Author Response
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Author Response File: Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsDear author, I found this paper is very innovative and of great importance.This manuscript gives a study on the ship wake simulation in fully-polarized SAR imagery and a large amount of SAR images have been simulated. And the new polarimetric enhancement method PDOF has been well applied to the simulated SAR imagery and obtained satisfying results. Besides a very comprehensive and applicable assessment criterion of the wake detection performance has been formulated and well-applied. I am very looking forward to the future research, such as the apply of the polarimetric enhancement and wake detection algorithm to the measured SAR images.The results and discussion based on measured data will be very attractive and interesting. Therefore，I recommend this article for publishing with a minor modification. This paper is very clearly written and the quality of English is good, but some sentences need to be modified. For example:
1. Page 6, “The main detection procedure for the HH, VV, HV polarizations and the PWF and PDOF SAR images are the same.” This sentence need to be modified.
2. Page 19, “The worst situation is that the wind speed is 14m/s, when the ship velocity is 6m/s, 8m/s, 10m/s and 12m/s respectively, the PMD of PDOF is 0.2278, 0.1722, 0.0889 and 0.1000, and the PFA of PDOF is 0.1333, 0.1222, 0.0611 and 0.0556.” I recommend the authors to separate this sentence into two.
Comments on the Quality of English LanguageGood
Author Response
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Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsThe paper deals with improvement in ship detection through wake pattern analysis based on full-polarimetry SAR. The topic is interesting, but the paper lacks various things. I tried to discuss them in my following comments.
1) The incorporation of full-polarimetry to enhance the analysis of ship wake patterns is not a new concept. Although there is a wealth of analyses and literature addressing this subject, several of them are not referenced within this paper. Please mention the state-of-the-art approaches and try to compare the performances with the proposed suggestion.
2) The methodology is validated with the simulated dataset. The real data-based analysis is missing here. It is crucial to acknowledge that the conclusions drawn here may undergo significant or partial alterations when evaluated in real-world scenarios.
3) The simulator description has to be provided in more depth conditions. How is the sea clutter modelled here simultaneously or individually, countering the incidence angle and wind speed (leading to a change in wave height)? The authors have presented a good analysis based on various conditions of incidence angle and wind speed; however, both, either simultaneously or individually, can impact the roughness of clutter, impacting the whole measurement. The simultaneous impact assessment is a difficult task. Please explain your comments on this in detail.
4) Ship monitoring requires frequent acquisition of the scenes and, therefore, requires revisiting time as soon as possible. Do you think exploiting other polarimetric SAR scenarios that transmit one and receive two orthogonal linear polarizations (dual-pol and compact hybrid-pol) will be beneficial as they have the benefit of wide swath coverage and shorter revisit time?
5) In line 70, the authors say, "Since the measured data is lacking in practice, the ship wake detection is often performed in simulated images." Please provide evidence on this. Nowadays, an enormous number of datasets are being released, and it is not hard to find real datasets for analysis. I recommend authors look for any real data and validate the proposed theory on it. Or at least mention some citations on the evidence that in recent papers of ship wake pattern analysis, the simulated datasets are in trend.
6) It is emphasised that "HV polarization" is not used in the previously reported literature. Please establish why this parameter is so important to be used and how it improves the results significantly in case of your implementation. Also, it will interesting to know your comment on the clutter modelling how you model clutter based on different polarizations, and what was the role of HV in that.
Comments on the Quality of English Language
Required corrections:
Please check the typos and grammatical errors and correct them throughout the paper. I have added a few of them below.
Line 443: Correct the line ". . . The simulated SAR imagery also indicate. . . " by replacing "indicate" with "indicates".
Line 449: Correct the line ". . . and sometimes there exists. . . " by replacing "exists" with "exist"
Author Response
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Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsThank you for your edits.
Here are my comments:
Figure 14, 15, and 16: it is not clear what is HHt or HHs. Maybe put the t and s in separate columns in the legend and add a title at the top of each column in the legend? Also, please add description of the plot in the figure caption that would describe the dotted lines not described in the legend.
Somewhere between lines 623 and 630 the authors should mention why the PMD is high for one wake type, and the PFA is high for all wake types.
Comments on the Quality of English LanguageNone.
Author Response
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Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for Authors1) Comment on the "Author's response provided on my 1st point": I can see the addition of new state-of-the-art papers as recommended. I am satisfied with the authors' response here.
2) Comment on the "Author's response provided on my 2nd point": Thank you for adding the analysis on real datasets. It proves the robustness of the methodology. I am satisfied with the response.
3) Comment on the "Author's response provided on my 3rd point": I can understand the difficulty and complexity behind explaining enormous possible aspects of wind, incidence and and clutter relationship. The added reference [26] is indeed useful here. I am satisfied with the authors' response.
4) Comment on the "Authors' response provided on my 4th point": In the response provided by the authors, it has been mentioned that the algorithm presented in this paper is adaptable for dual and compact-pol scenarios. I also agree with the author's point here, and I recommend mentioning this point in the paper. There are some methods that either approximate [1] or completely generate [2] the full-pol information from compact hybrid-pol SAR scenarios considering the reflection symmetry condition, which is valid in sea-based situations.
[1] M. M. Espeseth, C. Brekke and S. N. Anfinsen, "Hybrid-Polarity and Reconstruction Methods for Sea Ice With L- and C-Band SAR," in IEEE Geoscience and Remote Sensing Letters, vol. 13, no. 3, pp. 467-471, March 2016.
[2] A. Kumar, V. Mishra, R. K. Panigrahi and M. Martorella, "Application of Hybrid-Pol SAR in Oil-Spill Detection," in IEEE Geoscience and Remote Sensing Letters, vol. 20, pp. 1-5, 2023.
Discussing this point in the paper will open a future scope and highlight a new way of improving performance in the sense of frequent monitoring based on using different transmitting and receiving situations.
5) Comment on the "Authors' response provided on my 5th point" I can see the response under comment 2 that the authors found a real dataset with their rigorous effort and added an analysis based on it. I am satisfied with the comments provided by the authors.
Author Response
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Author Response File: Author Response.pdf
