Polarization Dependent Gain Stability of Raman Amplification Single-Core Feedback Structure Based on Consistency of Long-Axis Azimuths Variation

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The paper is about particular implementations of ROPA, in particular about polarization-dependent gain issues. 

The structure of the paper is adequate and the methodology is consistent. The English grammar needs revision, because of some minor typos and errors. The graphs need to be reworked, to be more clear (e.g., enlarge the fonts).

Overall, there are no evident flaws, and the results are confirmed by the experiments. 

 

Comments on the Quality of English Language

The English grammar needs revision, because of some minor typos and errors. 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The authors provided sufficient data and analysis in the manuscript. There are a few concerns over the content:

1. The measurement principle section can be improved by simplifying the decription and citing proper references.

2.  There are several typo/grammar errors that can be improved, please proof read carefully.

Comments on the Quality of English Language

There are several grammar errors. For instance, in line 319 '...the polarization state will still affected by temperature...'

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

In this article, the authors have developed a detailed comparison and analysis of polarization-dependent gain, elliptic angular rate and elliptic major axis azimuth in two types of systems, RFA-FRMOP and RFA-RMOP, for Raman amplifiers, which is a substantial amount of work. The topic is interesting and I recommend this paper, but the paper still needs to be revised and I have the following suggestions for reference.

1.     It is mentioned in Part 2 that the PDG characteristics are related to the change of polarization angle between the working light and the pump light, but there is no mention of the pump light parameter in Part 4 and Part 5, and whether the influence of the pump power, the pumping method, the fiber parameter, etc., on the PDG characteristics needs to be discussed as well.

 

2.     Throughout the article, light, working light, signal light and pump light are difficult to distinguish between their specific parameter properties (Part 2. working light in the text part and signal light in the picture caption), if possible through the spectral schematic or textual description. If possible, this can be illustrated by a spectrum or a textual description.

 

3.     The consistency of the change in PGD for the two optical paths in Part 4(Line 162) is difficult to read from the graphs, and it is recommended that the data be merged, and similarly figure 7 (h) and figure 8 (h) need to be digitally represented for the picture data.

 

4.     There are also some minor issues such as:

(1) It should be “Figure 4(I)”(Line 176 and Line 256) instead of “Figure 4(O)”;

(2) It is suggested to add RFA-FRMOP and RFA-RMOP to the name of the picture so that readers can distinguish them better;

(3) Figure 6 , Figure 8 should be shown in one page;

(4) Formula 3 is incomplete;

Please read through the manuscript carefully several times and pay attention to the details. Picture title description, article layout and so on should be improved.

Comments on the Quality of English Language

The language quality of this article is acceptable. 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

Technically sound paper.  Just a few grammatical corrections indicated in the attachment.

Comments for author File: Comments.pdf

Comments on the Quality of English Language

Quality of English is adequate.  A few corrections are suggested and marked in the attached document.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 3 Report

Comments and Suggestions for Authors

The author responded well to the previous questions and suggested that the article be accepted.