Performance Optimization of Multipair Massive MIMO Polarized Relay Systems
Round 1
Reviewer 1 Report
The contribution claimed by the Authors reads: “...proposed a dynamic weighted particle swarm optimization algorithm with contraction factor (CF-DWPSO) for polarization direction selection, distributed beamforming is used to effectively suppress or eliminate the inter-pair interference.”
Although, the manuscript is well written there is some important missing information.
a) The Authors exploit the channel model developed within COST 2100, however there is not any related cited references.
b) The COST 2100 model describes structure composed of clusters (Fig.2), but when this is utilized for the algorithm evaluation in section 4, such a structure is absent. The Authors should explain how the general case is restricted to the one used and what are the related restrictions imposed on their methodology.
c) In page 3 the Authors claim that “Each node of this model is equipped with multiple antennas. The transceiver is equipped with a dual-polarized antenna array, and the relay is equipped with a massive MIMO antenna array”.
However, in their implementation (Fig. 7) they simply depict a planar array with an inter-element distance of λ/2 (half wavelength).
d) Overall the Authors should describe a realistic structure – topology which should reflect their original claims, while they should point out how this fits to the assumed COST 2100 model, noting all the assumptions.
Author Response
Response to Reviewer 1 Comments
Dear Reviewers,
Thanks very much for taking your time to review this manuscript. I really appreciate all your comments and suggestions! Please find my itemized responses in below and my revisions/corrections in the re-submitted files.
Thanks again!
Point 1: The Authors exploit the channel model developed within COST 2100, however there is not any related cited references.
Response 1: Thank you very much for your review of my submission and your valuable suggestions. Your guidance is correct, and I should cite the relevant references in the article to clearly state that I used the COST 2100 channel model. Among the references, [23] [27] [28] [29] [35] are the relevant literature on the COST 2100 channel model.
Point 2: The COST 2100 model describes structure composed of clusters (Fig.2), but when this is utilized for the algorithm evaluation in section 4, such a structure is absent. The Authors should explain how the general case is restric ted to the one used and what are the related restrictions imposed on their methodology.
Response 2: Thank you very much for your review of my submission and your valuable suggestions. In response to your questions, we have explained the model structure used in the evaluation of the algorithm and the limitations associated with the general case in section 4 of the paper as well as in page 3.
Point 3: In page 3 the Authors claim that “Each node of this model is equipped with multiple antennas. The transceiver is equipped with a dual-polarized antenna array, and the relay is equipped with a massive MIMO antenna array”. However, in their implementation (Fig. 7) they simply depict a planar array with an inter-element distance of λ/2 (half wavelength).
Response 3: Thank you very much for your review of my submission and your valuable suggestions. We have modified the figure description of the polarization configuration of the antenna unit on this figure. And the structural setup of the antenna has been restated.
Point 4: Overall the Authors should describe a realistic structure topology which should reflect their original claims, while they should point out how this fits to the assumed COST 2100 model, noting all the assumptions.
Response 4: Thank you very much for your review of my submission and your valuable suggestions. In page 4 of the paper, we make suitable assumptions about the proposed mathematical model and the COST 2100 channel model, and we use the COST 2100 channel model to better describe the polarization distribution at the multipath cluster level, to introduce the polarization distribution model into the current MIMO channel, and this approach is also applicable to the polarization expansion of other MIMO channel models.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Authors investigated a polarization selection scheme for antenna arrays combining multipair massive MIMO relay and beamforming to improve MIMO relay channel quality. However, major corrections are required:
1. In abstract, please clearly specify the Purpose, Contribution, and findings.
2. Please provide a table in the related works section and comparison between present and exiting works.
3. Contribution part is not clear. Please more explain.
4. In fig. 1, notation as BS and R1-RT are confusing.
5. In the mathematical model, authors consider BS as Relay. Which type of relay used Amplify and Forward or Decode and Forward. Not clear description.
6. In eq. (13), typo error?
7. In eq. (18), typo error.
8. Please provide complexity analysis
9. It is recommended to use a professional proofread and native English correction.
It is recommended to use a professional proofread and native English correction.
Author Response
Response to Reviewer 2 Comments
Dear Reviewers,
Thanks very much for taking your time to review this manuscript. I really appreciate all your comments and suggestions! Please find my itemized responses in below and my revisions/corrections in the re-submitted files.
Thanks again!
Point 1: 1.In abstract, please clearly specify the Purpose, Contribution, and findings.
Response 1: Concerning your comments on the abstract, I apologize for the oversight of not clearly stating the purpose, contributions, and conclusions. I fully understand the importance of clearly highlighting these aspects in the abstract to provide a comprehensive overview of the study. To solve this problem, I have revised the abstract accordingly to include specific statements. I believe this revision will greatly enhance the clarity and impact of the manuscript.
Point 2: Please provide a table in the related works section and comparison between present and exiting works.
Response 2: Thank you very much for your review and valuable comments on my manuscript. Regarding the requirement of comparing existing works with previous works, this paper provides a comparison of the performance optimization of existing polarization optimization algorithms (DWPSO and regular polarization optimization algorithms) and non-polarization optimization algorithms with the CF-DWPSO polarization optimization algorithm proposed in this paper for multi-pair large-scale relay channel systems in section 4. In section 3 of this manuscript, we also introduce the algorithm design and the implementation process in detail, hoping that the introduction of these two parts can make the readers further understand the connection and difference between them.
Point 3: Contribution part is not clear. Please more explain.
Response 3: Thank you very much for your review of my submission and your valuable suggestions. We give an introduction to the paper and the optimization strategy used in page 2 in paragraph 2 and give the contribution of this paper.
Point 4: In fig. 1, notation as BS and R1-RT are confusing.
Response 4: Thank you very much for your review of my submission and your valuable suggestions. For this problem, we have re-represented the relay nodes in fig. 1.
Point 5: In the mathematical model, authors consider BS as Relay. Which type of relay used Amplify and Forward or Decode and Forward. Not clear description.
Response 5: Thank you very much for your review of my submission and your valuable suggestions. For that issue, we have written in the modeling in section 2, "As assumed in [30], there is no direct link between transmitters and receivers, and each transmitter communicates with its corresponding receiver with the help of all relays with amplify-and-forward (AF) ." The type of relays we used and the associated parameters are consistent with [30].
Point 6: In eq. (13), typo error?
Response 6: I would like to thank you very much for pointing out the error in eq. (13). I apologize for the inadvertent error, and I will make immediate corrections to ensure that eq. (13) is spelled correctly. I will carefully review and proofread all equations in the paper to ensure that they are properly presented and formatted in the text.
Point 7: In eq. (18), typo error.
Response 7: Thank you very much for your review of my submission and your valuable suggestions. We have corrected the error in eq. 18.
Point 8: Please provide complexity analysis
Response 8: Thank you very much for your review and valuable comments on my manuscript. Regarding the requirement of complexity analysis, we have added an analysis of the complexity of the CF-DWPSO algorithm in paragraph 2 of section 4.1.
Point 9: It is recommended to use a professional proofread and native English correction.
Response 9: I am very grateful for your suggestions regarding professional proofreading and native English proofreading for my paper. I recognize the importance of accuracy of linguistic expression in an academic paper, especially for non-native English speaking authors. To ensure that my paper meets high quality linguistic standards, we have revised the paper for issues of grammar, word choice, and sentence structure by working with a professional proofreader.
Author Response File: Author Response.pdf
Reviewer 3 Report
The topic of this manuscript entitled: "Performance Optimization of Multipair Massive MIMO Polarized Relay Systems" falls within the profile and scope of the Electronics.
Recommendation – Consider after minor changes
Comment:
In the work two polarizations (H and V) were consider to improve the efficiency of m-MIMO array.
Authors should reveal what type of antennas were used (linear, microstrip .. ) and what is the antenna configuration geometry (separation distance). The mutual antenna coupling should be discussed (isolation vs correlation). It is recommended to add any photo of the array
Author Response
Response to Reviewer 3 Comments
Dear Reviewers,
Thanks very much for taking your time to review this manuscript. I really appreciate all your comments and suggestions! Please find my itemized responses in below and my revisions/corrections in the re-submitted files.
Thanks again!
Point 1: In the work two polarizations (H and V) were consider to improve the efficiency of m-MIMO array.Authors should reveal what type of antennas were used (linear, microstrip .. ) and what is the antenna configuration geometry (separation distance). The mutual antenna coupling should be discussed (isolation vs correlation). It is recommended to add any photo of the array.
Response 1: Thank you very much for your review of my submission and your valuable suggestions. I am honored to have the opportunity to respond to your comments and will incorporate your suggestions to improve my article. in page 9 of the article, we reveal the type and configuration of the antenna array used.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
My previous comments are marginally addressed.
Author Response
Dear Reviewers,
Thank you very much for reviewing and evaluating my submission. We take your comments very seriously and will do my best to improve to meet your requirements. We apologize for the fact that the highlighted revision was incorrectly identified in some places due to the large number of changes we made to the manuscript. For you and the reviewers to better see the changes, we will additionally submit a manuscript and a revised latex and pdf source file. Below we will explain the highlights of the revision:
- The red font is a modification and explanation of reviewer 1 comments
- Black are unmodified
After careful review, I have made some adjustments and modifications to your previous comments to better respond to your comments. Below are my specific responses to the comments you made:
Point 1: The Authors exploit the channel model developed within COST 2100, however there is not any related cited references.
Response 1: Thank you very much for your review of my submission and your valuable suggestions. Your guidance is correct, and I should cite the relevant references in the article to clearly state that I used the COST 2100 channel model. Among the references, [23] [27] [28] [29] [35] are the relevant literature on the COST 2100 channel model.
Point 2: The COST 2100 model describes structure composed of clusters (Fig.2), but when this is utilized for the algorithm evaluation in section 4, such a structure is absent. The Authors should explain how the general case is restric ted to the one used and what are the related restrictions imposed on their methodology.
Response 2: Thank you very much for your review of my submission and your valuable suggestions. In response to your questions, we have explained the model structure used in the evaluation of the algorithm and the limitations associated with the general case in section 4 of the paper as well as in page 4. The COST 2100 model is just an effective way to introduce polarization at the moment, but it doesn't mean that your method is limited to this model, if there are other models that can also expand polarization, then your method can be applied to these models as well.
Point 3: In page 3 the Authors claim that “Each node of this model is equipped with multiple antennas. The transceiver is equipped with a dual-polarized antenna array, and the relay is equipped with a massive MIMO antenna array”. However, in their implementation (Fig. 7) they simply depict a planar array with an inter-element distance of λ/2 (half wavelength).
Response 3: Thank you very much for your review of my submission and your valuable suggestions. We have modified the figure description of the polarization configuration of the antenna unit on Fig. 8(b). And antenna isolation is guaranteed in this configuration, So the polarization selectivity of the entire antenna array can be spatially configured by superimposing the polarization selectivity of individual antennas.
Point 4: Overall the Authors should describe a realistic structure topology which should reflect their original claims, while they should point out how this fits to the assumed COST 2100 model, noting all the assumptions.
Response 4: Thank you very much for your review of my submission and your valuable suggestions. In page 4 of the paper, we make suitable assumptions about the proposed mathematical model and the COST 2100 channel model, and we use the COST 2100 channel model to better describe the polarization distribution at the multipath cluster level, to introduce the polarization distribution model into the current MIMO channel, and this approach is also applicable to the polarization expansion of other MIMO channel models.
Author Response File: 
Author Response.docx
Reviewer 2 Report
Thanks for correction. But still now some corrections are missing.
1. In eq. (13), typo error? why put first and second bracket both. First bracket is enough.
2. Fig. 10 should be correction. SNR(dB) is NOT clear. Also Fig. 10(b) legend is missing.
Okay
Author Response
Dear Reviewers,
Thanks very much for taking your time to review this manuscript. I really appreciate all your comments and suggestions! Please find my itemized responses in below and my revisions/corrections in the re-submitted files. Below we will explain the highlights of the revision:
- The bluefont is a modification of reviewer 2 comments
- Black are unmodified
Thanks again!
Point 1: In eq. (13), typo error? why put first and second bracket both. First bracket is enough.
Response 1: I would like to thank you very much for pointing out the error in eq. (13). I apologize for the inadvertent error, and we have corrected the error in eq. (13).
Point 2: Fig. 10 should be correction. SNR(dB) is NOT clear. Also Fig. 10(b) legend is missing.
Response 2: Thank you very much for your review of my submission and your valuable suggestions. We will reprocess the plot to ensure that the SNR values are clearly visible in the image and have added the Fig. 10(b) legend.
