Angle Estimation for MIMO Radar in the Presence of Gain-Phase Errors with One Instrumental Tx/Rx Sensor: A Theoretical and Numerical Study
Round 1
Reviewer 1 Report
Dear Sir,
I have several comments regarding your paper which I suggest to consider revising:
- The English needs to be improved by a native speaker. Sentences like
Line 30 " eager for" and " line 31 " representatives" are not the right words for the meaning you wanted etc.
- The math was not checked and the simulation parameters are well presented however the authors should go over and pay attention if mistakes fall in their paper.
- The Math should be written in a more easy way to make the paper easy for the readers.
I think the authors did hard work but the method is simulative only. I am not sure if I understood correctly if noisy input was simulated to the simulation and if it is related to real-life parameters. If not I think it is good to have such data.
Sincerely yours
Comments for author File: 
Comments.pdf
Author Response
Please find in the attached file.
Author Response File: Author Response.pdf
Reviewer 2 Report
The paper “Angle estimation for MIMO radar in the presence of gain-phase errors with one instrumental Tx/Rx sensor” suggests a technique for estimation of arriving and departure angles using MIMO, bi-static radar. A theoretical analysis and numerical simulations are presented.
The subject is interesting. However, the merit of the work is not clear. The authors should explicitly explain the novelty of their approach and the major features of the proposed technique.
Moreover, although some theoretical basis is presented, including an important review of tensor analysis, it will be helpful if the fundamental principle of DOD and DOA estimation procedure is described in a simplified way, expressing the transmitted and received signals, the processing in the receiver and addressing the origin of gain-phase errors leading to accuracy degradations in the positing estimation (with which the presented technique claims to deal with).
I may suggest to present the physical quantities (e.g. the inter-element spacing d, the DOD and DOA angles, number of elements M and N, etc.) in Fig. 1, illustrating the of bi-static MIMO radar.
Also – all the terms and quantities should be defined. What are a_t, a_r ? Are they representing only phase shifts due to distances ?
It is not clear if the analysis considers moving targets. Frequency shifts can emerge due to the Doppler effects. How it is expressed in the theory ? Please elaborate.
I would ask the authors to carefully review their paper and verify that the meaning of each quantity used along the derivation is well defined. I found too many parameters appearing in the txt that are not clearly presented and explained.
The signal to noise ratio should be defined.
The improvement in the estimation due to the suggested procedure must be concluded more quantitatively.
Author Response
Please refer to the attached file.
Author Response File: Author Response.pdf
Reviewer 3 Report
Please analyze and show the performance of the method versus different ranges for phase and gain errors.
Author Response
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Author Response File: Author Response.pdf
Reviewer 4 Report
In the intro there is no info about radar waveforms what is essential to understand rest of the paper. In (1) x is not defined and there is no info about range what is essential for bi-static measurements. Self calibration process in not clearly explained. The distance between tested algorythms and CRLB is bbig, and this phenomena is not explained in the paper. The MUSIC and ESPRIT algorythms usually performs quite well - so explanation while it faild in the presented case is needed - it can be introduced starting from ideal case and then comming to more distorted oneAuthor Response
Please refer to the attached file
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
Please note Comment 8: "The improvement in the estimation due to the suggested procedure must be concluded more quantitatively. "
It is expected to extend the conclusion section to summarize the resulted improvements of the study.
Author Response
We have added more quantitatively conclusions in the simulation sections as follows:
- For Figure 2: It is seen that the RMSE performances corresponding to ESPRIT-like, RD-MUSIC and PARAFAC-like are at least an order of magnitude higher than the proposed estimator, and they barely vary with the increasing SNR.
- For Figure 3: Compared with ESPRIT-like, RD-MUSIC and PARAFAC-like, the RMSE of the proposed estimator is about 10 dB lower.
- For Figure 5: It can be found in Figure. 5 that the run time that RD-MUSIC required is at least 10 dB higher than the proposed estimator. Besides, the run time of our estimator is similar to that of PARAFAC-like (the gap is smaller than 5 dB), and the proposed estimator is more efficient than ESPRIT-like for large scale array.
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
