Dynamic Scattering Approach for Solving the Radar Cross-Section of the Warship under Complex Motion Conditions

Round 1

Reviewer 1 Report

In this paper, the authors propose a new dynamic scattering approach based on physical optics and physical theory of diffraction to provide an electromagnetic scattering characteristics of warship in the presence of complex motion conditions. In particular, a deep study on the effect of many parameters on the proposed model has been conducted, viz., observation angles, turret rotation, hull attitude changes and sea wave models.

The paper is overall well-written and clear if it needs to be somehow improved. I have the following suggestions to improve it as listed below. The main advantage of the proposed method is on the observed results from analyses. The main point of weakness is the presentation/organization of the manuscript. For instance, as to section 2, probably, it should be better to directly give the results, leading all mathematical derivation in an appendix. Otherwise, it is difficult to understand how to apply the proposed method.

To help the readers in understanding the paper, I suggest adding a Notation section at the beginning of the paper. In particular, please, use always the same notation inside the paper, e.g., boldface for matrices, and so on. Once you have defined all the used notation in a preliminary section, the text will be more fluid in its reading. In addition, define all symbols in this section, e.g., the symbol x for the vectorial product, etc.

Please, enlarge the brackets in eq. (18).
Most of figures are a bit blurred, therefore I suggest improving their quality in the revised version. Precisely:
- Fig. 1: some variables are indicated with a very light color; therefore, they are very difficult to be read. I suggest using black color for all the texts. This consideration is valid also for the other figures.
- Fig. 3, please improve the quality of lines within the graphs. They are blurred, and I have some difficulties in understand in which points the curves overlap. This is the same also for the remaining figures.

Conclusion section should be expanded. First of all, the authors need to summarize the novel contribution of the manuscript, then provide some comments on obtained results, and, finally, they have to add some suggestions for possible future works.

In this paper, the authors propose a new dynamic scattering approach based on physical optics and physical theory of diffraction to provide an electromagnetic scattering characteristics of warship in the presence of complex motion conditions.

The paper is overall well-written and clear. I have only some minor suggestions to improve it as listed below.

First of all, I suggest adding a Notation section at the beginning of the paper. In particular, please use always the same notation inside the paper, e.g., boldface for matrices, and so on.

Most of figures are a bit blurred, therefore I suggest improving their quality in the revised version.

Finally, please, enlarge the brackets in eq. (18).

Author Response

 

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Brief summary:
This work proposes an computational electromagnetics approach to tackle with the issue of RCS estimation for a moving warship, taking into account the rotation of the main gun turret, as well as the surface waves. This approach is based on physical optics and physical theory of diffraction. Several cases are examined and the estimated RCS values are presented as functions of time or azimuth.

General comments:
Having followed a similar previous work by the authors, I was quite accustomed to their dynamic scattering approach and their methodology. However, their introduction was somehow confusing, referring to a large number of papers (approximately 40 references within 40 lines of text), while it was not so clear what is the contribution of this work. A reader who is not so familiar with the dynamic scattering method might have a hard time trying to follow the proposed approach.
Their methodology concerning the warship & turret model is quite clear and well presented.
Concerning the results, I would appreciate a more detailed discussion in the conclusion section, summarising their findings.

The introduction is a bit chaotic: a lot of relevant papers are involved. However, it is not so clear what is the relation and the contribution of the proposed approach.

lines 122-126: The trigonometric function sea (TFS) wave model and the simplified regular sea (SRS) model seem somehow arbitrary. One or two references would be helpful, unless the authors believe that these models are quite standard and straightforward.

lines 134-135: There are some symbols in these equations, such as k, R and J, which are not properly defined. Even though one who is familiar with the relevant literature would understand their meaning, I think that they should be defined. Otherwise, a proper reference would be also helpful.

line 164: Some rephrasing is required.

line 165: I suppose that QSP means "quasi-static principle" but it should be noted and it should be explained.

line 182: It is not clear what "local mesh encryption" is.

line 252: Delete one "the". Also, please consider "important factor", instead of "practical factor".

Author Response

Please see the attachment.

 

Author Response File: Author Response.pdf