Combined Shark-Fin Rooftop Antenna for LTE, WLAN and BeiDou Applications

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Authors present rooftop automobile antennas incorporating a main antenna and a diversity antenna. The devices have been simulated, fabricated and characterized. The work is interesting but some improvements are necessary before publication, as follows: 

- In the introduction section, Authors reported examples of antennas from the literature. Please add a paragraph about the possibility to use for this aim also a Dielectric resonator antennas with pros and cons of this kind of antenna by referencing: 

1) Cheh Lin IK, Jamaluddin MH, Gaya A. A Triple Band Substrate Integrated Waveguide with Dielectric Resonator Antenna for 4G and 5G Applications. Micromachines. 2023; 14(7):1284. https://doi.org/10.3390/mi14071284

2)X. -H. Ding, Q. -H. Zhang, W. -W. Yang, W. Qin, L. Guo and J. -X. Chen, "A Dual-Band Antenna for LTE/mmWave Mobile Terminal Applications," in IEEE Transactions on Antennas and Propagation, vol. 71, no. 3, pp. 2826-2831, March 2023, 

3) Marrocco V, Basile V, Marasco I, Niro G, Melchiorre L, D’Orazio A, Grande M, Fassi I. Rapid Prototyping of Bio-Inspired Dielectric Resonator Antennas for Sub-6 GHz Applications. Micromachines. 2021; 12(9):1046. https://doi.org/10.3390/mi12091046

- What kind of optimization authors performed on the antenna's geometry? Please describe.

-What about the simulation of the connector used for the measurements? 

-The discrepancy between simulations and measurements is high for both gain and S11 parameter. the fabrication tolerances should give less discrepancy between them. Please take into account the presence of the connector and the losses of the dielectric substrate in the simulations.

-Authors report the measured polar plots of E-plane and H-plane. Please add a dot line of the simulated polar plot in figure 12 - 13- 14- 15 as a comparison. 

 

Comments on the Quality of English Language

Minor editing of English language required

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The manuscript is prepared in well manner. Below are some comments:

include the error percentage margin in the abstract section

mention the vswr effect too

mention the brief description of each sections in introduction part.

extend the figure 2

plot the vswr too

show the radiation pattern in 2d plot

 

Author Response

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Reviewer 3 Report

Comments and Suggestions for Authors

The topic of this manuscript entitled: "Combined Shark-Fin rooftop Antenna for LTE, WLAN and Bei-Dou Applications" falls within the profile and scope of the Electronics.

Recommendation – Consider after minor changes

Comments:

In the work the rooftop automobile antenna has been presented. Authors presented two antennas - the main antenna and orthogonally located diversity antenna.

1. The question is what was the philosophy of the antenna geometries design. Whether the inspiration was to obtain the broad frequency band or suitable polarization or omnidirectional radiation? The problem is that authors didn’t explain scientifically why they applied such antenna geometries. If the geometries are only the result of technical computer simulation investigation without any electromagnetic justification then the scientific soundness is poor.

2. The envelope correlation coefficient is not small. Why is that ? May be this is because of the common metal-base.

3. What about the metal roof of the car. How it influences the antenna patterns.

4. Both antennas are not located close to himself. If such system is treated as one antenna then the phase distance of received signals can be too large. On the other hand if antennas operate as MIMO system then such array should be more explained how this will be operated in the car.

Author Response

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Author Response File: Author Response.docx

Reviewer 4 Report

Comments and Suggestions for Authors

This paper introduced a roof-mounted automobile antenna for LTE and navigation system applications. The main features of this proposed design are compactness and good performance. The paper is presented in an appropriate manner and is well-organized. Professionals handle the design evolution, simulation, experimental validation, and performance comparison with previously published work.

I recommend the authors to add more recent references from reputed journals , which would enhance the performance comparison table.

Comments on the Quality of English Language

The quality of English language is good.

Author Response

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Author Response File: Author Response.docx