Axial Ratio and Gain Enhancement of a Circular-Ring Slot Antenna Using a Pair of Asymmetrical Rectangular Slots and a Parasitic Patch for a Radio Beacon on a Nanosatellite

Round 1

Reviewer 1 Report

see attached file

Comments for author File: Comments.pdf

Author Response

Note :   1. All new correction in green color

            2. English grammar also was corected my friend who understand english better. 

Answer to Reviewer 1

There have been so many similar papers published in this topic area. This is just another one even if the authors say that the proposed antenna allows to have an Axial Ratio and Gain Enhancement. Nevertheless, I encourage the authors for making additional work following recommendations before submitting a revised manuscript.

- My recommendation is that the paper is rewritten oriented to this interest compared to the others

cited by the authors which are referenced by number [1-2] in terms of dimensions, RL and AR bandwidths.

Ans : Thank you very much for your comment.

-          In line 416, I already changed the sentence be `The proposed CSA with two unsymmetrical rectangular slots and a parasitic patch has the higher peak gain compared to Ref [6,7,8] and the broader 3-dB ARBW compared to Ref [8,10] `

-          In Line 283-292, I consider the symmetrical AR in frequencies of 2.2 and 2.4 GHz as function of theta. This is not considered in the other papers.

- Moreover, the paper is rewritten oriented to this interest for the nanosatellite applications or so you have to remove “Nanosatellite” in the title.

            Ans:

-          I changed the title with added `Radio Beacon on`

-          I changed the abstract with added in line 17-19, in line 19-21, in line 23 and in line 32.

-          I changed the Introduction, in line 38-44, In line 47-50, 60.

In particular, what is the bidirectional radiation interest?

Ans: In Line 47-48. The small satellite has no the attitude and stabilization control. Overcoming the problem will install two antennas orthogonally on the satellite to enhance the stable handshaking from the satellite to the receiver in ground.

What is the desired limit of the coverage?

Ideally, isotropic antenna for nanosatellite is good, but the antenna gain is very small, so the better choice is bidirectional radiation, with 2 antennas installed orthogonally.

Show the AR pattern directly on several cut planes. What is the impact on the 3-dB ARBW?

The several cut planes are showed in Figure 6, in frequencies of 2, 2.2 and 2.4 GHz, in phi (                                               ) of 0, 45 and 90 degree, respectively as the variable of theta ().

-          In frequency of 2 GHz, while Phi = 0 degree, the AR is not perfect symmetrical, and the AR is higher than 3dB. While Phi = 45 degree, the AR whose lower than 3 dB is shifted to theta of -31 degrees and 57 degrees. While Phi = 90 degrees, the AR whose lower than 3 dB is shifted to theta of -39 degrees.

-          In frequency of 2.2 GHz, while Phi = 0 degree, the AR not perfect symmetrical but the AR whose lower than 3 dB are from theta -35 to 56 degrees. While Phi = 45 degrees, the AR whose lower than 3 dB are from theta -35 to 57 degrees. While Phi = 90 degrees, the AR whose lower than 3 dB is shifted to theta of -14 degrees

-          In frequency of 2.4 GHz, while Phi = 0 degree, the AR is almost symmetrical in theta of 0 degrees. The 3dB is from -33 degrees to 37 degrees. While Phi = 90 degrees, the AR whose lower than 3 dB is almost symmetrical in theta of 0 degrees from of -18 degrees to 17 degrees.

Is it possible to have a good revolution symmetry of AR and radiation patterns with the proposed antenna?

-          In frequency of 2 GHz, while Phi = 0 degree, the AR not perfect symmetrical but the higher than 3dB.

-          In frequency of 2.2 GHz, while Phi = 0 degree, the AR not perfect symmetrical. The 3dB is from -35 degrees to 56 degrees.

-          In frequency of 2.4 GHz, while Phi = 0 degree, the AR not perfect symmetrical. The 3dB is from -33 degrees to 37 degrees.

The detail of the simulated result is showed in figure 6

- In line 65 and 107, two design parameters (Rs, t) are not explained or indicated in the geometry

of CSA

            Ans:     Thank you very much for your correction. Parameter Rs be R in line 84, and parameter t is the copper thickness added on line 87.

- In line 150, 228, …279, reduce the number of decimal (for example, 1.92 dBic in stead 1.921

dBic)

            Ans: Done

- In Line 271, what do you mean by “Model 3”

            Ans: Already corrected be Model 2. After revision, be In line 320

- In line 274, the simulated IBW is not lower than measured IBW? (see figure 7.a)

Ans: Thank you very much for your very careful correction. Corrected. Now be in line 323-325.

- Change axis labels in figures 7.

            Ans: Done. Now be figure 9

- The authors present the AR and antenna gain in the figure 7. Is it boresight AR? Is it the max value of the realized gain or boresight?

Ans: the AR and the Gain are the realized AR and the realized Gain, respectively. Now be figure 9

- In line 338, review the sentence “The proposed CSA with two unsymmetrical rectangular slots

and a parasitic patch has broader 3-dB ARBW” compared by the [1] et [2].

Ans:     Thank you very much for your correction. I already changed the sentence be `The proposed CSA with two unsymmetrical rectangular slots and a parasitic patch has the higher peak gain compared to Ref [6,7,8] and the broader 3-dB ARBW compared to Ref [8,10].` Now in line 416-418.

Author Response File: Author Response.pdf

Reviewer 2 Report

(1) This paper proposes circular-ring slot antenna with a pair unsymmetrical rectangular slots and a parasitic patch for axial ratio and gain enhancement in the nanosatellite application. It is an interesting design and has some publishable materials. Similarly, as another solution for low-profile waveguide antenna with high performance, substrate integrated waveguide (SIW) slot antennas also exhibit the features for bandwidth and gain enhancement applications. Include, if possible, it is useful to reference recent papers with SIW structures in Introduction so that readers can identify the related papers and track the progress of related field easily.

[1] G. Q. Luo, Z. F. Hu, W. J. Li, X. H. Zhang, L. L. Sun, and J. F. Zheng, “Bandwidth enhanced low profile cavity backed slot antenna by using hybrid SIW cavity modes,” IEEE Trans. Antennas Propag., vol. 60, no. 4, pp. 1698-1704, 2012.

[2] Z.Q. Xu, J.H. Liu, S. Huang, and Y.X. Li. Gain-enhanced SIW cavity-backed slot antenna by using TE410 mode resonance. International Journal of Electronics and Communications (AEÜ), 98, 68–73, 2019.

2. The authors should give the E-filed distribution figure for the proposed design.

Author Response

Note :   1. All new correction in green color

            2. English grammar also was corected my friend who understand english better. 

Answer to Reviewer 2

(1) This paper proposes circular-ring slot antenna with a pair unsymmetrical rectangular slots and a parasitic patch for axial ratio and gain enhancement in the nanosatellite application. It is an interesting design and has some publishable materials. Similarly, as another solution for low-profile waveguide antenna with high performance, substrate integrated waveguide (SIW) slot antennas also exhibit the features for bandwidth and gain enhancement applications. Include, if possible, it is useful to reference recent papers with SIW structures in Introduction so that readers can identify the related papers and track the progress of related field easily.

[1] G. Q. Luo, Z. F. Hu, W. J. Li, X. H. Zhang, L. L. Sun, and J. F. Zheng, “Bandwidth enhanced low profile cavity backed slot antenna by using hybrid SIW cavity modes,” IEEE Trans. Antennas Propag., vol. 60, no. 4, pp. 1698-1704, 2012.

[2] Z.Q. Xu, J.H. Liu, S. Huang, and Y.X. Li. Gain-enhanced SIW cavity-backed slot antenna by using TE410 mode resonance. International Journal of Electronics and Communications (AEÜ), 98, 68–73, 2019.

            Ans:  Thank you very much for your comment. In line 60, I referred paper “the Gain-enhanced SIW----"

2. The authors should give the E-filed distribution figure for the proposed design.

            Ans: Thank you very much. I added Figure 7 for electric field distribution.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

see attached file

Comments for author File: Comments.pdf

Author Response

Answer to Reviewer 1.

The paper has been revised and improved by the Authors, according to the comments and suggestions. It has been found suitable for publication. Some new comments are included. Please take those into account when preparing the final version of the manuscript for publication.

- Table 2: reduce the number of decimals

        Ans: Done. Thank you

- Figure 6.a-b: Give a conclusion instead of commenting on the figure (line 285- 294).

            Ans: Thank you very much. I already corrected, in line 286-290

    Why the measured AR vs θ is not represented?

            Ans: Done, in E and H-plane. It is presented in figure 6

- Table 3: why a column on |S11| is not shown and compared?

            Ans: S11 = IBW (Impedance Bandwidth), in 4th column.

- The answer of the first comment "The authors present the AR and antenna gain in the figure 7.

    Is it boresight AR?

            Ans: No, that is the realized AR

    Is it the max value of the realized gain or boresight ?

           Ans: Yes, that is the max value of realized gain

Thank you very much for your correction to make my paper better

My best regards,

Peberlin Sitompul

Author Response File: Author Response.pdf