Review Reports

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The overall idea of this paper is interesting, but the implementation has significant problems. The modal-based design of a system is, indeed, superior, but requires the clarification of many important aspects. In this work, these aspects are examined superficially. The comments are the following:

1. The six triangular patch units are separated by a thin line? If no, why they are considered a different units?
2. How is eq.(2) for modal weighting coefficients extracted? Is there a proper reference to clarify this relation?
3. Again in eq.(2), the numerator seems to be the inner product between the mode current and the excitation field. It must be stated explicitly in the manuscript. What about the symbol for the denominator? Is it, also, an inner product? Of what?
4. How are the eigenvalues extracted for eq. (2) and (3)? What parameters are required for the simulation problem?
5. In eq.(3) it seems that something is missing since the MS depends only on the lambda. But if this is true, what it means that the mode is closer to the resonant state?
6. It seems that the eigenvalue analysis computes the induced currents. What's the methodology to compute the modal radiation patterns?
7. How is it related that mode 1 and mode 5 are connected vehicle safety (lines 128-129)? Why the other modes are not involved?
8. In the reflection coefficient of Fig. 6a, there are two resonances at 3GHz and ~3.4GHz. How is the existence of this second resonance clarified (mode 2 is over 3.5GHz)?  
9. The measurement results for the radiation patterns are not visible. The curve shall be changed to something clearer.
10. A comparison table with other similar antennas (e.g. dual band) must be included.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

In this manuscript, the author proposes  a dual-band dual-mode antenna without complex feeding network via CMA method. The simulation and measurement results verify its validity. I have some comments on it, shown as follows.

[1] Can author add a Cartesian coordinate in Figure 3 because x direction is mentioned in the manuscript? It will make reader to understand mode current easier.

 

[2] Can author add clarify the detail on how to excite Mode 1 and 5 through Port1 in the manuscript? For example, the excited voltage and port information for Port 1 so that the reader will easier to understand how the different modes work in the proposed antenna in reality.

 

[3] Please label the Port 1 and 2 in the Figure 1 because the author includes the mode excitation via different ports in Figure 4.

 

[4] Can author add more details for the feeding network part in Figure 2 and 5 because the author mentions this manuscript proposes a dual-band dual-mode antenna without complex feeding network? For example, some picture and explanation related to feeding network analysis.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors did a good job of improving their paper. However, there are still some comments to take into account:
1) The CMA solver of CST is used to calculate the eigenmodes for the problem. This must be stated explicitly in the manuscript. Moreover, it is mentioned that the eigenvalue equation is derived by the method of moments impedance matrix. But in this part, the electromagnetic quantities are considered (electric and magnetic field), not lumped quantities (voltage and current). So, how is the impedance matrix related?
2) Is there a proper citation that relates the communication scenario (mid-range and long-range) to the radiation pattern? How is this specification defined? It must be stated explicitly in the manuscript.
3) The comparison table has a column "Feeding network complexity". Why is this only important? In particular, in this work, there are many via holes that increase the overall complexity. Giving as a specification only the feeding network is not quite fair. A more proper (and fair) metric shall be given.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Thank you for author's effort. I don't have more questions on the revised manuscript.

Author Response

Thank you very much for your positive feedback and for confirming the revisions. We sincerely appreciate your time and effort in reviewing our manuscript, which has greatly helped us improve the work.

We are pleased that the revised manuscript addresses your concerns satisfactorily.