Wireless Communication System Performance in M2M Nakagami-m Fading Channel

Round 1

Reviewer 1 Report

1.       Figure .1  should be more descriptive of the proposed system model

2.       Most of the integrals in the manuscript need to be justified and simplified more in the manuscript. For example

·         Eq. (3) the authors  should explain how they get (3) based on their suggested system

·         Integral (4), and  (6) should have  proof.

The reviewer urges the authors to improve the manuscript by offering the critical steps for each mathematical integral proof.

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Reviewer 2 Report

The overall impression from the presented submission is quite mixed. The text is well-written and well-formatted. The authors' logic and all the derivations are clear. The obtained results are somewhat interesting. But there are several issues with the submission.

             Major issues.

            1. For such a widely used channel model, the reference section is very shallow and outdated. It must be greatly expanded.    

 

            2. The performed analysis (in Section 4) is very superficial and gives no new insight for the reader. 

3. The authors must state the unique contribution of their submission. It seems to me that the authors omitted (maybe unintentionally) a wide range of closely resembling research papers from their colleagues, see, for example,

[Ref 1] D. Č. Pavlović, N. M. Sekulović, G. V. Milovanović, A. S. Panajotović, M. Č. Stefanović, and Z. J. Popović, “Statistics for Ratios of Rayleigh, Rician, Nakagami-m, and Weibull Distributed Random Variables,” Mathematical Problems in Engineering, vol. 2013. Hindawi Limited, pp. 1–10, 2013. doi: 10.1155/2013/252804.

[Ref 2] E. Mekić, M. Stefanović, P. Spalević, N. Sekulović, and A. Stanković, “Statistical Analysis of Ratio of Random Variables and Its Application in Performance Analysis of Multihop Wireless Transmissions,” Mathematical Problems in Engineering, vol. 2012. Hindawi Limited, pp. 1–10, 2012. doi: 10.1155/2012/841092.

[Ref 3] D. Krstic, M. Głąbowski, M. Stefanovic and M. Peric, "Level Crossing Rate of Ratio of Product of Two Rayleigh and One Nakagami-m Random Variable and of Ratio of Rayleigh and Product of Two Nakagami-m Random Variables," 2018 11th International Symposium on Communication Systems, Networks & Digital Signal Processing (CSNDSP), 2018, pp. 1-6, doi: 10.1109/CSNDSP.2018.8471843.

[Ref 4]   I. Vulić, D. Krstić, P. Nikolić, S. Minic and M. Stefanović, "Average Fade Duration of Triple Nakagami-m Random Process and Application in Wireless Relay Communication System," 2019 4th International Conference on Smart and Sustainable Technologies (SpliTech), 2019, pp. 1-5, doi: 10.23919/SpliTech.2019.8783094.

……..  and many, many others.

             So, what bothers me most is what new knowledge did the authors bring with this submission?

            The results for the first-order statistics are not new at all, and the stronger results exist (including bivariate distributions and correlated cases).

            The results for the second-order analysis is also not novel (see at lease [Ref 3]). The Laplace approximation in the same form (and even notation) was used in the multitude of papers.

All of the above makes the whole submission questionable.

  

Minor issues.

            4. It is evident that the authors used an assumption of the independence of the fading links, but nowhere in the text it is stated. It must be disclosed explicitly, since it shrinks possible applications.

Please, in the expressions, avoid usage of the “dot” symbol. For multiline equations, use “times” symbol at the end of the line and at the beginning of the consecutive line.

5. Several times within the text, while performing double integration, the authors switch the integration order without proper justification. This must be rectified.  

6. No initial parameters’ limitations are set, but implicitly (from (13)) it is evident that at least “mx” and “my” are assumed to be integer. This greatly limits the applicability of the derived results, since it excludes an important case of hyper-Rayleigh fading (m=0.5) (i.e., the most severe fading).

7. On 3 lines in Fig.4, no markers can be found (for zth=2).

8. The references must be appended with DOI.

9. The results (analysis and simulation) are given in terms of the signal envelope (z) and envelope threshold (zth). But from the practical point of view, it is more significant to have the results parametrized in terms of the signal-to-noise ratio. Thus, such a conversion is expected.

Author Response

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Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

The authors did a good job in expanding their review part. But still there are several issues that must be cleared out.

1. The equations are the part of the sentences. This means that they must be followed by the corresponding punctuation marks.

2. The point that was not rectified is the justification of integration order interchanging. Again. Several times within the text, while performing double integration, the authors switch the integration order without proper justification. The authors simply stated it “as is”. This is not the way it is done. Fubini–Tonelli would be just fine, but this must be done.

3. There are plenty of grammar and punctuation errors still left. Please, correct them.

- in line 131, “… sinusoid a Nakagami-m…” → “… sinusoid as a Nakagami-m…”;

- in line 133, “…interference limited…” → “… interference-limited…”;

- in line 93, “… second order…” → “… second-order…”;

- in line 161, “… In [32–35] graphically presents results ??

etc….

4. The issue with the incremental contribution is still on the table. The authors agreed that the stronger and more general results exist. So what are the benefits from their research?

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Round 3

Reviewer 2 Report

The submission can be accepted in present form.