Wearable Directional Button Antenna for On-Body Wireless Power Transfer
, Yiying Wang 1,* and Omar M. Ramahi 4
Round 1
Reviewer 1 Report
In the manuscript, the authors investigate a wearable directional button antenna with AMC cells. There seems to be some lack of information. The reviewer recommends the authors add an explanation of the implementation and evaluation.
1. The materials and implementation method of the prototype need to be described to enable readers to make follow-up experiments.
2. The quantitative performance comparison with existing antennas needs to be described.
Author Response
The authors thank you for your valuable comments, we reply them one by one according to the change track version as follows.
Question: In the manuscript, the authors investigate a wearable directional button antenna with AMC cells. There seems to be some lack of information. The reviewer recommends the authors add an explanation of the implementation and evaluation.
Answer: We add the explanation on how to design the AMC cells as the new formulas (1)~(3) on page 3. We can evaluate the corresponding performance according to the concerned resonance.
Question:1. The materials and implementation method of the prototype need to be described to enable readers to make follow-up experiments.
Answer: We simply describe the corresponding fabrication process in the first paragraph of sub-section 3.1 as ‘Here, the all-fabric microstrip line is made by pasting the conductive textile with the proper size cut by knife on the aforementioned 100% cotton substrate, then the bottom circular-disc substrate is put on the microstrip line, the rest parts, including the mon-opole, AMC cells, and the top-loaded substrates, are determined finally.’ The corresponds to the research idea of first paragraph of sub-section 2.1.
I think the readers can repeat our work according to the above description.
Question:2. The quantitative performance comparison with existing antennas needs to be described.
Answer: We compare our work with other works presented in the ‘Introduction’ except [34], and listed in Table 3 on page 7. The work of [34] is just the button-like antenna, it is not the conventional button antenna with the post in between.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
-The experimental bandwidth of the antenna (1.07 GHz) is wider than the simulated one (0.37 GHz). However, in practice, simulation results are better than experimental data. This vast difference needs more clarification. Please comment.
-The discrepancy in the realized gain illustrated in Fig. 10. is relatively high around 5.75 GHz. Please address the issue and its interpretation.
-There are several typos and errors that should be corrected.
A few examples are:
Line 231: "is much more complexity"
Line 287: "On the contrary"
Line 290: "Conclusions" (Conclusion is preferred).
please carefully edit the manuscript.
Author Response
The authors thank you for your valuable comments, we reply them one by one according to the change track version as follows.
Question:-The experimental bandwidth of the antenna (1.07 GHz) is wider than the simulated one (0.37 GHz). However, in practice, simulation results are better than experimental data. This vast difference needs more clarification. Please comment.
Answer: If the substrate is the conventional ‘hard’ material not the textile, the simulated is generally better. However, the measured is better for the textile owing to the difficulty of simulation for this material. And the air gap of textile makes the lower quality factor and thus the wider bandwidth. We explain this in the second paragraph on page 6.
Question:-The discrepancy in the realized gain illustrated in Fig. 10. is relatively high around 5.75 GHz. Please address the issue and its interpretation.
Answer: The maximum difference appears around 5.75 GHz as you said. That’s because the non-uniformity of textile becomes significant at the lower frequencies which is inevitable. In fact, when we implement the measurement, we have to touch the substrate of textile, and this process will lead to the change of textile, such as the height, the uniformity etc. However, the difference is less than 1 dB which means the agreement between the simulation and measurement. We add the explanation in the second paragraph on page 7.
Question:-There are several typos and errors that should be corrected.
A few examples are:
Line 231: "is much more complexity"
Line 287: "On the contrary"
Line 290: "Conclusions" (Conclusion is preferred).
please carefully edit the manuscript.
Answer: Thank you for your careful comments. We have modified your mentioned error, like ‘much more complex’. And we correct some other parts, such as the lines of 75-78, the last sentence of first paragraph on page 6 ‘slope detail is presented (not present)’. You can find many other parts. Thanks again.
Author Response File: Author Response.pdf
Reviewer 3 Report
1. The authors should explain how they have selected the presented AMC structure and how its parameters are evaluated and why a 2 x 3 array was selected, design equations should be added.
2. What is the advantage of using F4BTM substrate?
Author Response
The authors thank you for your valuable comments, we reply them one by one according to the change track version as follows.
Question:1. The authors should explain how they have selected the presented AMC structure and how its parameters are evaluated and why a 2 x 3 array was selected, design equations should be added.
Answer: The AMC is the metamaterial which has good performance shortening the distance between the source and reflectors. We didn’t explain this in the manuscript owing to it’s just the common thing. However, we add the design formulas (1)~(3) to determine the AMC cells on page 3. After defining the resonance, we can determine the corresponding size by careful design.
Besides, we add the explanation of the 2 x 3 array in the line 75, that’s for the reduction of height or lower-profile purpose comparing with the 3 x 3 array published in another paper.
Question:2. What is the advantage of using F4BTM substrate?
Answer: The F4BTM is the Chinese material, like the Rogers one. We choose it owing the cheap price. It’s the conventional material which can be found in someone else’s work. Thus, we didn’t explain in the manuscript. However, if you feel we should add this explanation inside, we will do soon.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
The manuscript has been well-revised. Especially the performance comparison in table 3 would be valuable information for readers. The reviewer has no other comment.
Reviewer 2 Report
No further comments.
Reviewer 3 Report
The authors have addressed all the queries.
