A Wide-Band High-Efficiency Hybrid-Feed Antenna Array for mm-Wave Wireless Systems

Round 1

Reviewer 1 Report

In the manuscript entitled "A wide-band high-efficiency hybrid-feed antenna array for mm-wave wireless system", the authors carried out an hybrid feed composed of coaxial line feed and aperture coupled feed to achieve broad bandwidth of ME antenna array. 
After carefully going through the manuscript, I found the work was well presented and organized. Also, the measured results are good agreement with simulated results.

However, in my opinion, this article in the present form is not suitable for publication.
The following mandatory suggestions to improve the quality of the paper should be taken into account by the authors

1) Even though the authors presented the reference for ME antenna [13], it is better to describe the operation principle and wireless performance of single ME antenna.

2) After optimization of detailed dimension, the authors show dimensions of proposed ME dipole sub-array at Table. 1.
However, the design procedure including initial dimension is needed for reader in view of wavelength.

3) In Table. 3, the result of 16X16 array should be marked as simulation.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Please see the following for my comments. Thanks.

Since the hybrid-feed structure is the major distinction/highlight of the paper, more relevant discussion and simulation results should be added. Moreover, I suggest the whole design flow should be broken down a bit, instead of directly (or only) presenting the whole structure with the optimized design parameters. Things like the design details of the transitions [RGWG to dielectric cavity (the coupling slot), dielectric cavity to the coaxial-feed ME-dipole (the probe)] should be discussed.

Please label the different heights (hx, as shown in Fig. 1a) in Fig. 1b as well, which could help the readers match the two figures. It is a bit confusing in current form, as figure 1a seems to be a 3-layer structure, while figure 1b clearly shows four instead. 

The spacings between adjacent ME-dipoles are marked as xd and yd in Fig. 1c, but expressed as xm and ym in the context. Please check.

The legend for "equal power" and "unequal power" should be swapped in Fig. 4. Please check.

Please include a measurement setup picture.

Figure 10 is mistakenly referred as Figure 12 in the context. Also, please explain the different percentages shown in Figure 10.

In the conclusion, it says the measured results show a max. radiation efficiency of 80%. Please explain the method used to measure the radiation efficiency.

Please further polish the language as there are some typos in the manuscript, such as "By combing the coaxial-line feed ...",  "... are all use ...", etc.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

According to the review report, the authors have made the peer-to-peer review. I have no further comments.