A Ka-Band Two-Channel Two-Beam Receiver Based on a Substrate-Integrated Suspended Line

Round 1

Reviewer 1 Report

Authors described one practical solution and presented achieved / measured results. In order to be considered for publication, the manuscript needs to be improved in following aspects:

1. To provide all data necessary for repetition of design by other researchers (measures, dimensions, etc.) since their practical implementation represents the main reported contribution.

2. Some comparison with other (referent?) values for the same frequency range should be provided within discussion / conclusion.

3. Idea presentation and design should be followed with better technical preparation of manuscript (all terms properly defined - like w and mi_zero in page 5, references addressed in text - like [15], [16], [17] which are not, h2 size in Fig. 4 seems inconsistent, etc.).

4. English should be carefully checked once again.

English should be carefully checked once again. See, for example, page 4: it looks like "to regard" was used instead of "to consider", "alone" instead of "along", etc.

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

Based on substrate-integrated suspended-line (SISL), authors proposed a two-channel two-beam receiver for miniaturization and high performance of phased array antennas.

The multilayer microwave substrate forms a multilayer spatial distribution of RF circuits, low-frequency circuits, and multilayered components, eliminating discontinuities caused by circuit interconnections and forming a three-dimensional multilayer assembled structure. Furthermore, multiple cavities are formed in which active devices can be embedded to shield microwave radiation signals, resulting in substantial interference reduction, self-packaging, and excellent electromagnetic compatibility between various microwave signals. 

The references are updated.

It would be better if Figure 8 was divided into two figures to make it more clear.

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

I have the following comments and recommendations to the paper:

— Abstract: The abbreviation “CLTE” is not defined. Moreover, in my opinion, there should not be abbreviations in the Abstract at all, because the abstracts are frequently published separately.

— Abstract, line 15: “<2.6 dB”: I am not sure whether it is sufficient. I saw many devices with the noise figures well below 2 dB in these frequency bands… Please include a brief discussion somewhere in the article about it.

— Introduction, line 26: “a small number”. How many (in percentage, e.g.) approximately?

— Line 42, “[6-13]”. I don’t like such “mass” citations; please define what is concretely in these publications.

— Line 55, Ka-band: Not all readers know these bands. Please define (here) which frequencies you operated concretely. (28–30 GHz as in line 102?)

— Lines 109–123: It seems to me that another achievement of the paper consists in a series of construction improvements. Is it true?

— Equation (1): Terrible typing of equations, you have 12pt size in equations comparing the 10pt size of the text. It should be 10pt size of both, MathType or similar editors easily enable it!

— Equation (4): It is an error here, the last member is not multiplied by any permittivity… — Equation (6): Extraordinarily ugly typing…

— Line 154, “20 GHz –40 GHz, no resonance”: Personally, I am a little in doubt whether there is no resonance in 15 GHz-wide band! (It is a contradiction with my experiences.)

— Figure 8(c): Please explain relatively high noise-figure fluctuation in this narrow band. (I have no idea why it is changing so much.)

Generally, in my opinion, the paper contains new results and could be published after minor (but important!) corrections. 

English is quite OK, in my opinion.

Author Response

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Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Authors did invest efforts in order to respond on my previous comments. Thank you, I have no further comments. All the best in future work.