Design and Performance Evaluation of a Compact Frequency-Reconfigurable Coplanar-Waveguide-Fed Slotted Patch Antenna for Multi-Band Wireless Communication
Round 1
Reviewer 1 Report
A reconfigurable CPW antenna is reported in this work. It is quite impressive for the five reconfigurable bands by tuning the PIN diodes. However, the current version still contains quite a few major concerns, which should be claimed clearly before further consideration.
1. As the Abstract and maintext emphasized, by tuning the diodes, five distinct frequency bands can be achieved. However, it should be noted that these five bands are interferenced, and their FBW values are quite differently. Hence, the authors should evaluate carefully for the five bands, especially setting up a general criterien to judge the five bands, for instance, peak gain/return loss/efficiency all reaching specific values. Otherwise, the results will vary heavily.
As shown in Figure 8, the peak gain varies from 2.5dBi to nearly 6dBi in various bands, this is unsuitable. Moreover, in Figure 12, the peak gain varies from 1.8dBi to 5.5dBi, with even much larger variation.
2. In Figure 10 and 14, only the simulated radiation patterns are given, while the measured radiation patterns are missing. It is really essential for the authors to add the measured radiation patterns. Please note, even the measured return loss, peak gain and efficiency results are in very good agreement with their corresponding simulations, the radiation patterns might have notable difference between simulation and measurement, since it is more related to the parameter Phase. Actually, for antenna design, radiation patterns will be the most significant parameters, even more important than other parameters. Furthermore, as the authors state in the manuscript, from Figure 7 and 11, there are difference between the measured and simulated S11, particularly, for the results in Figure 11, the measured S11 is much worse than the simulation, which means the radiation pattern and efficiency will be much different.
3. It is much better for the authors to given the radiation efficiency, total efficiency and return loss simultaneously.
4. In Table 4, the proposed work with five bandwidths as 2760MHz, 480MHz, 5300MHz, 670MHz, and 900MHz. In fact, the bandwidths of 2760MHz and 5300MHz are really too large, thus making their fractional bandwidth will be extremely large consideration that the center frequency is less than 13GHz. Hence, please check carefully for the radiation efficiencies of the five bands within their bandwidth. Generally, such wideband bandwidth means low efficiency.
Author Response
Please see the attachment
Author Response File: 
Author Response.pdf
Reviewer 2 Report
This paper demonstrates the design of a compact frequency-reconfigurable CPW-Fed slotted patch antenna for Multi-Band Wireless Communication. Here are my comments
1- The paper has limited contributions.
2- The design procedures should be added.
3- Why did the authors choose these frequency bands?
4- The gain of the antenna is small, especially at higher frequency bands add discussion
5- Figures should be discussed in more detail.
6- New references from 2022-2023 should be added and compared with the author's design.
7- The equivalent circuit model should be added.
Moderate editing of English language required
Author Response
Please see the attachment
Author Response File: Author Response.pdf
Reviewer 3 Report
A reconfigurable CPW based flexible multiband antenna is proposed.
1. Add the coordinate axis along with the antenna geometry.
2. Both simulated and measured radiation patterns should be shown under on and off condition of the switch.
3. Show the current distribution under on and off condition.
4. Add measured gain results.
5. Mention the novel contributions clearly and also add a paragraph in the introduction establishing the need for the proposed antenna.
6. In the comparison table it is advisable to compare only reconfigurable antennas.
Please also refer to some other CPW based flexible antennas:
a. Flexible CPW fed transparent antenna for WLAN and sub‐6 GHz 5G applications
b. Interconnected CPW fed flexible 4-port MIMO antenna for UWB, X, and Ku band applications
c. High Gain Flexible CPW Fed Fractal Antenna for Bluetooth/WLAN/WPAN/WiMAX Applications
7. Although flexible antenna is proposed, no results under bending conditions are shown.
Please check for some typos and grammatical mistakes.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
no more comments
Reviewer 2 Report
The authors replied to all comments.
Reviewer 3 Report
The comments are well addressed and implemented in the revised manuscript.
