Research Progress on Carrier-Free Phase-Retrieval Receivers

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This paper reviews the latest progress of CF-PR receivers designed for high-speed optical short-reach transmission links. This paper is interesting and the paper is well organized. The reviewer has some additional comments listed below for the further improvement.

 

1、For the CF-PR receiver with parallel alternating projections discussed in Section 3.1.1, how many dispersion planes are optimal?

2、What are the advantages of CF-PR compared with the CAPR scheme proposed in Ref. [1]?

3、What new problems will be introduced with the increase in the number of delays for the ST diversity scheme?

4、Figure 6 in the manuscript has a confusing layout.

Comments on the Quality of English Language

Moderate editing of English language required

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The authors have provided a well-organized comprehensive review of recent progress of carrier-free phase retrieval receivers, based on their previous solid experience on related research topics. The paper reads well, and only minor concerns are listed below:

1.      In some figures, e.g., Fig. 5, 6, and 7, the authors are suggested to reduce the font size.

2.      It would be beneficial to discuss the trends and challenges/future directions of carrier-free phase retrieval receivers in the conclusion section.

3.      Please consider including the following works in the paper, which is also relevant and from this journal.

[1] Wu, Q.; Xu, Z.; Zhu, Y.; Zhang, Y.; Ji, H.; Yang, Y.; Qiao, G.; Liu, L.; Wang, S.; Liang, J.; et al. Machine Learning for Self-Coherent Detection Short-Reach Optical Communications. Photonics 2023, 10, 1001. https://doi.org/10.3390/photonics10091001.

[2] Karar, A.S.; Falou, A.R.E.; Barakat, J.M.H.; Gürkan, Z.N.; Zhong, K. Recent Advances in Coherent Optical Communications for Short-Reach: Phase Retrieval Methods. Photonics 2023, 10, 308. https://doi.org/10.3390/photonics10030308

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

After careful examination, I regret to inform you that I cannot recommend the paper for publication in its current form. My assessment leads me to conclude that the contribution lacks the necessary level of novelty required for publication in photonics. Is it a review article? The overall Manuscript writing is very confusing in terms of the author's own contribution. The findings presented, while valuable, do not significantly advance the existing body of knowledge in the field. I encourage to reconsider the framing of the research or explore additional dimensions that could introduce a more novel perspective.

Comments on the Quality of English Language

n/a

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The author has  responded my questions. The paper canaccepted for publication.

Comments on the Quality of English Language

 Minor editing of English language required.

Author Response

Thank you very much for your kind consideration of our manuscript.

Reviewer 3 Report

Comments and Suggestions for Authors

Please include a more detailed explanation of the technical basis underlying carrier-free phase retrieval receivers, especially concerning their ability to address chromatic dispersion-induced power fading in short-reach optical fiber communication.

How does the presented research build upon or diverge from existing work?

What are the main contributions or advancements highlighted in the research progress of carrier-free phase retrieval receivers? It is suggested to include a section by highlighting the main contributions.

In the context of optical field recovery, how does carrier-free phase retrieval (CF-PR) receiver compares with other direct detection schemes mentioned, such as KK, ASCD, CADD, and SVR, in terms of technical efficiency and performance metrics?

Could the author elaborate on the specific role and impact of the dispersive element in the CF-PR receiver configuration for field recovery of quadrature amplitude modulation (QAM) signals?

What is the underlying mechanism employed by the CF-PR receiver for recovering the optical field of QAM signals, and how does this mechanism relate to its effectiveness in short-reach transmission links?

Does the work provide quantitative performance metrics, such as signal-to-noise ratio (SNR) or bit error rate (BER), to assess the efficacy of CF-PR receivers in comparison to other direct detection schemes?

How effectively does the CF-PR receiver eliminate the need for a strong continuous-wave (CW) optical carrier in comparison to other schemes, and are there specific conditions where It may face challenges.

Does the CF-PR receiver demonstrate adaptability to various quadrature amplitude modulation (QAM) schemes, or are there limitations in terms of the modulation formats it can effectively recover?

 

Are there any integration challenges or compatibility issues associated with implementing CF-PR receivers in existing optical communication systems, particularly in the context of high-speed short-reach transmission links?

Comments on the Quality of English Language

N/A

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 3

Reviewer 3 Report

Comments and Suggestions for Authors

The authors have diligently addressed the concerns raised during the review process, and the manuscript now meets the standards for publication.

Comments on the Quality of English Language

N/A