A Novel Inserting Pilot Radio over Fiber System without the Bit Walk-Off Effect for the Generation and Distribution of Frequency 16-Tupling Millimeter Waves by Mach–Zehnder Modulators

Round 1

Reviewer 1 Report

In this manuscript, the authors developed a novel inserting pilot scheme to create 16-tupling frequency MMW ROF system, eliminating the bit walk-off effect induced by fiber chromatic dispersion. In comparison with the conventional MMW ROF system, the proposed design provides reduced power penalty and advanced Q factor. The analyses conducted are comprehensive and reasonable. This manuscript is organized well. However, before making this manuscript acceptable for publication, the authors are required to address the following comments well.

1. Provide the full name of MZM, FBG, and FMF when they are mentioned for the first time.

2. Please find the following sentences to remove the grammatical issues.

1. Last sentence in the abstract section.

2. Line 257-258.

3. Line 288.

4. Line 342-343

3. Please add SPACE between value and unit.

Based on the abovementioned comments, this manuscript is recommended for minor revision. A revised manuscript is required.

Please check the comments for authors.

Author Response

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Reviewer 2 Report

This paper researches a novel inserting pilot ROF system without bit walk-off effect for generation and distribution of frequency 16-tupling millimeter wave by MZMs，gives the appropriate principle and method, and carries on the simulation verification, however, there are still some problems in this paper, which suggest further revision.

(1) In part2, the principle is not explained clearly, combined with Figures 1 and 2, the author should give a suitable mathematical representation function to describe it.

(2) How does the mathematical model in Part 3 relate to Part 2? An explanation should be given

(3) The author has done some simulation, what is the actual experimental result? Simulation alone cannot explain the innovation of the paper.

(4) The paper lacks necessary comparative verification.

(5) In part1, what innovations should the author give in this paper? The current description does not show what problem this paper solves.

(6) Although this paper has done some research, I think it is not innovative in methodology.

The expression of some sentences in this paper needs to be improved

Author Response

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Reviewer 3 Report

A novel inserting pilot ROF system without bit walk-off effect for generation and distribution of frequency 16-tupling millimeter wave by MZMs

Authors: Xu Chen, et al

The manuscript proposed novel scheme for generating and distributing frequency 16-tupling millimeter-wave (MMW) radio over fiber (ROF) system without the bit walk-off effect by using Mach-Zehnder modulators (MZMs).

Overall, the paper has promising application prospects in ROF systems due to its ability to mitigate bit walk-off effects, enhance system performance, and increase transmission distance. Howeever, It would be great if it is mentioned a bit more about experimental impelementation may be needed to fully realize its potential.

 The manuscript is well generally written but needs substantial improvement by proofreading and providing a more complete exposure to the field. I would suggest the author give more comprehensive citations in the description for advancing photonic frequency multiplication techniques for mm-wave signal generation.

Author Response

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Reviewer 4 Report

The authors have presented a new design of an inserting pilot radio over fiber system for 16-tupling mm wave using Mach Zender modulators in parallel to each other. This system exhibits elimination of bit walk-off effects. The paper is well structured, and then methodology is described systematically. The results arising from the simulations make the proposed communications architecture a promising one. The paper can be considered for publication in Photonics after the authors have addressed the following minor issues:

1. In Table 1, the values put in column 3 should be mentioned in the manuscript as assigned values or computed values.  For example G = 6 and Vpi = 4V appear in the table and the manuscript but it is not clear whether it was just assigned or is it computed.

2. Starting with Figures 3 to 8 and then in Figures 11 and 12, the authors should make the captions more descriptive. For example: "Fig. 3. Optical spectrum of point A in Figure 1" should be revised to "Figure 3. Optical spectrum at the output of the 8th order sideband generator (Point A) in Figure 1." The main goal here is to have the general reader have the ease of looking at the results without going back and forth to Figure 1 to find out where to look for the spectrum.

Once the authors have made these minor corrections, the paper should be considered for publication in Photonics.  

The manuscript needs a thorough run-through of spelling checks as there are a number of misspelling incidences.

Author Response

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Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

This paper has been modified basically according to the questions raised, and the author has added appropriate content. The structure and research ideas of the current version of the paper are clearer, and the description of the highlights of the paper is also supplemented. At the same time, the author has also done some supplementary analysis on the experimental verification. I think this paper can be published.