Application of Quasi-Continuous Waveform Coding in Spaceborne Synthetic Aperture Radar
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThis paper presents a good idea about applying a new quasi-continuous wave system in spaceborne SAR. The paper makes detailed simulations and gives comprehensive evaluation results to prove the idea. Therefore, I recommend that this manuscript can be accepted after considering the following issues.
1）The exploration of aligned continuous wave SAR has been going on for more than 30 years. Its advantages and disadvantages are clear. Although this article gives a detailed background and describes its advantages, it does not elaborate on how to avoid the disadvantages. Please explain in detail how your algorithm avoids the shortcomings of previous techniques.
2）The results of many different experiments are presented in this article. Do they belong to the same coding model? If they are different, I think different coding models should be presented separately.
3）The word " synthetic aperture time " appears a lot in the article, which is a typical Chinglish. This is not proper non. I never found it in the references. You can use “integration time”. Please proofread the use of technical terms throughout the text to ensure that they are understandable to native English speakers.
4）I noticed that your article is not only simulation, please indicate the source of your real data of mountains.
5）I noticed that your idea comes from Academician Wang's paper published in 2019. Please explain what innovations you have made on the basis of his theory.
6）The article mentioned that your algorithm is used before imaging. I wonder why not apply it after imaging to reduce the floating point operations per second(FLOPS).
Comments on the Quality of English LanguagePlease carefully proofread the manuscript to avoid grammatical mistakes.
Author Response
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Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsQuasi-continuous wave radar is an attempt to give consideration to the performance of pulse and continuous wave radar signals. This paper aims to add a new quasi-continuous wave coding method for spaceborne synthetic aperture radar (SAR) systems. However, this paper needs to be revised significantly before it can be accepted.
First of all, this paper lacks the necessity of using quasi-continuous wave coding method for spaceborne SAR system, that is to say, what problems do we want to solve in spaceborne SAR by using quasi-continuous wave coding method?
Secondly, this paper introduces the status quo of many quasi-continuous wave coding methods in the introduction. Can these coding methods be used in spaceborne SAR systems? If not, what are the reasons? If you can use it, compare it with the method presented in this article
Finally, the writing of the paper needs to be strengthened, for example, the literature [1]-[6] has not been cited; Line 49 of page 2 appears [?], and so on. None of this is easy to understand.
Author Response
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Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for Authors
1. This paper studies on improving the quality of spaceborne synthetic aperture radar imaging using quasi-continuous waveform coding. The paper provides useful information that has good practical significance. The results are satisfactory.
2. The paper is generally written well. Some editing and clarifications are recommended, as mentioned below.
3. In the title, delete "Research on the".
4. In the Abstract, for the second "synthetic aperture radar (SAR)", just use SAR (deleting synthetic aperture radar),
5. Line 49, add the reference in [?].
6. Line 113, change S[ L] to SL
7. For Equation (2), define m and l. Does 0 mean "no emision"?
8. In the text in Line 150, it uses ":", but in Eq.8 it uses ";", please be consistent.
9. Define M in Eq. 12.
10. For Fig. 6, use a different and more specific subtitle to distinguish (a) and (b); as well as (c) and (d). Also for Fig. 7, (c) and (d).
11. Fig. 10, provide the unit for the y-axis.
Comments on the Quality of English LanguageSome minor editing is needed.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
Comments and Suggestions for AuthorsNo
