Origami Fresnel Zone Plate Lens Reflector Antennas for Satellite Applications

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

In Eq. (1), the variable 'M' inside the square root should be 'm'. Also, it should be mentioned that 1<= m <= M

In Eq. (2) inside the square root, 'D_m' should be replaces with 'D_M'

Comments on the Quality of English Language

The text on Figures (2) & (3) must be improved to be clearer. 
There are many typos and grammar errors. Double check the language of the paper. 
Also, in scientific writing, it is not suitable to use future tense as mentioned at the beginning of Sec. 3. 

Author Response

Thank you for your suggestions aimed at improving the quality of our work. In the following, we’ll try to answer your concerns:

(1) In Eq. (1), the variable 'M' inside the square root should be 'm'. Also, it should be mentioned that 1<= m <= M In Eq. (2) inside the square root, 'D_m' should be replaces with 'D_M'

[1.1] We provided to correct the mistakes. Thank you for the indication.

(2) The text on Figures (2) & (3) must be improved to be clearer.

[1.2] We provided to improve the text of Figs 1 and 2 as suggested. Thank you.

(3) There are many typos and grammar errors. Double check the language of the paper.

[1.3] We provide an accurate review of the whole text. Mistakes and grammatical errors have been corrected. Thank you.

(4)Also, in scientific writing, it is not suitable to use future tense as mentioned at the beginning of Sec. 3. Article - please, check that all the used abbreviations are defined. 

[1.4] Thank you for your constructive comment. We provided to remove the future tense sentences, and we checked all the considered abbreviations.

Reviewer 2 Report

Comments and Suggestions for Authors

The authors have presented an origami Fresnel zone plate lens reflector antenna designed for satellite applications. The reviewer offers the following comments:

1. The abstract and conclusion sections require improvement, with greater emphasis on the key contributions and performance metrics of the proposed design. For instance, quantitative results such as gain enhancement and side-lobe level reduction should be clearly highlighted.

2. The quality of the figures, particularly Figures 1 and 3, should be improved to enhance clarity and readability.

3. A brief discussion on origami antennas and their suitability for satellite communication is recommended in the Introduction section to provide better context and motivation.

4. The authors should specify the loss tangent of the Kapton substrate used in the design.

5. There are typographical errors in the conclusion section. For example, the sentence “This section is not mandatory, but can be added to the manuscript if the discussion is unusually long or complex” seems misplaced. The manuscript should be carefully proofread to eliminate such errors.

Author Response

Thank you very much for your constructive suggestions. In the following, we'll try to address your concerns.

(1) The abstract and conclusion sections require improvement, with greater emphasis on the key contributions and performance metrics of the proposed design. For instance, quantitative results such as gain enhancement and side-lobe level reduction should be clearly highlighted.

[2.1] Thank you for your constructive suggestions. We provided better descriptions of the key contributions in the abstract and conclusion sections. 

(2) The quality of the figures, particularly Figures 1 and 3, should be improved to enhance clarity and readability.

[2.2] We provided to improve the quality of Figs 1 and 2 as suggested. In particular, the text has been increased to make it more readable. Thank you. 

(3) A brief discussion on origami antennas and their suitability for satellite communication is recommended in the Introduction section to provide better context and motivation.

[2.3] Thank you for your constructive suggestion. We tried in the introduction section to better specify the suitability of origami antennas for satellite communication. Thank you.

(4) The authors should specify the loss tangent of the Kapton substrate used in the design.

[2.4] We provided the loss tangent of the Kapton material. Thank you.

(5) There are typographical errors in the conclusion section. For example, the sentence “This section is not mandatory, but can be added to the manuscript if the discussion is unusually long or complex” seems misplaced. The manuscript should be carefully proofread to eliminate such errors.

[2.5] Thank you for your accurate suggestions. We provide an accurate review of the whole text. Mistakes and grammatical errors have been corrected

 

Reviewer 3 Report

Comments and Suggestions for Authors

The comments are in the attachfile.

Comments for author File: Comments.pdf

Author Response

Dear reviewer, in the following we'll try to answer to your concerns.

 (1) Regarding the novelty of combining Moriyama origami with Fresnel zone plates for reflector design, how does this approach address limitations in existing deployable antennas for satelliteapplications, such as mechanical fragility or bulkiness, and why was Moriyama specifically chosen over other origami patterns? 

[3.1] Yes, this is true. There are different versions of origami structures; for example, different interconnected sections of the Triangular Cylindrical Origami structure could be used to implement the antenna feeder. We decided to choose the Moriyama structure because, in our opinion, it is simpler with respect to the other origami structures. Thank you for the constructive comment. 

(2) In the mathematical formulation for the Fresnel lens design, how do Eq (1) to (3) ensure accurate phase correction across subzones, particularly for N=16, and what validation was performed to confirm that the calculated radii in Table 1 achieve optimal focusing at 15 GHz? 

[3.2] Thank you very much for your suggestions that permit us to explain this important aspect better. The choice of the N subzones is a compromise between the accurate phase correction and the limited available physical dimension, typical of a small cube satellite. The number of N=16 Fresnel subzones offers a good compromise that permits accomplishing good phase corrections despite the limited dimensions. We provided a better specification of this important aspect in the description of the mathematical formulation.    

(3) Considering the experimental results showing a gain reduction from 19.0 dBi in the standard configuration to 17.5 dBi in the origami prototype, how does this performance degradation impact the antenna's suitability for Ku-band satellite links, and what measures were taken to assess deployment repeatability under thermal cycling? 

[3.3] The gain reduction is quite limited, and the impact of the gain degradation has limited effects on Ku-band satellite links. Concerning the deployment repeatability, it is worth noticing that the antenna structure has been studied to be deployed after the satellite reaches the operational orbit, but it is not expected to recompact the antenna. Also, because once activated, the considered linear actuator cannot recompact the antenna structure.We provided a better specification of this important aspect.  

(4) For the Nitiniol-based actuators used in deployment, what evidence supports their long-term reliability in space environments, such as resistance to radiation or microgravity effects, and how was the 500mA current threshold optimized to prevent overheating while ensuring consistent shape recovery? 

[3.4] Yes, we agree with the reviewer, we forgot to mention how the current value of 500 mA has been optimized. As indicated by the reviewer, this value has been chosen because it ensures the overheating prevention of the actuator and the damage to the antenna structure. We provided to specify this important aspect. Thank you. 

(5) When comparing the S11 performance between origami and non-origami versions, how does this impedance mismatch influence overall system efficiency in satellite transceivers, and were return loss measurements repeated across multiple prototypes to account for fabrication tolerances? 

[3.5] The considered Ku frequency band belongs to the centimetric wavelength, and the fabrication tolerances are limited to a fraction of the wavelength. Thanks to this, the effects and the antenna’s radiative properties are limited, as demonstrated by the comparisons between origami and non-origami structures. We provided a specification of this important aspect in the section devoted to the antenna prototype description. We provided a better explanation in the body of the manuscript. Thank you. 

(6) In the context of future work, what specific optimizations are planned to mitigate the observed beamwidth increase in the Yoshimura feeder, and how will scalability to higher frequencies or smaller nanosatellite form factors be addressed without compromising gain? 

[3.6] It is worth noticing that for higher frequency bands, the fabrication tolerances, especially for the Yoshimura feeder, become significant and could produce a strong reduction of antenna performances, especially for the Yoshimura feeder. A possible solution to avoid this problem is the use of cmbined metallic dielectric structures. Thank you.  

(7) While the literature review discusses several existing technologies, it would benefit from including more recent advancements. Recent studies [1][2] emphasize the critical application of some novel type of antenna, which should be discussed.[1] Improving Age of Information for Covert Communication with Time-Modulated Arrays.[2] Self-powered absorptive reconfigurable intelligent surfaces for securing satellite-terrestrial integrated networks. 

[3.7] Thank you for your constructive suggestion. We provided further information and references related to the technologies that you kindly indicated.

Round 2

Reviewer 3 Report

Comments and Suggestions for Authors No further questions.