Miniaturized Dual-Band Bandpass Filter Using T-Shaped Line Based on Stepped Impedance Resonator with Meander Line and Folded Structure

Round 1

Reviewer 1 Report

Dear Authors, 

Thanks for the presented work, this shows a miniaturized dual bandpass filter with improved performance. Yet, there is a couple of items that need to be cleared out throughout the paper as follows:

1. Please include the fabricated sensor's picture in your paper.
2. What is the definition of Z_v and Z_d in Fig. 2(a). Please verify the notations throughout the text.
3. Please elaborate exactly the intended sections of Z₂, Z_t, and Z_s on Fig. 1 and 3.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Dear Authors, 

Thanks for the giving me the scope to review this paper. Please see the following comments I thought would be helpful for this paper. Here are those comments. 

 

General comments:

All figures should have axis orientation.

In terms of simulation and measurement comparison, all solution frequency, center frequency, frequency band should be the same

 

 

 

 Line 24: The insertion and return losses of the first frequency passband (fo1) are 0.09à is it dB or just the number

Line 27:  The insertion and return losses of the second frequency passband (f02) are 0.21 à is it dB or just the number

In general, both must be very low (0) at this frequency of operation

 

Line 52: The SIR structure is expressed as open stubs with low and high impedances. --> you need a very clear clarification why as such

 

Line 123: you are comparing 2.8 GHz with 2.85 GHz and showing the same bandwidth.  Ideally, the frequency band the center frequency should be the same. That needs to be corrected.

Best of luck, hope to see the improved version. 

Thank you!

Author Response

Dear Authors, 

Thanks for the giving me the scope to review this paper. Please see the following comments I thought would be helpful for this paper. Here are those comments. 

Answer: Thanks to your careful review, I was able to revise my paper to a better condition. Thank you very much for the opportunity to make corrections.

General comments:

All figures should have axis orientation.

In terms of simulation and measurement comparison, all solution frequency, center frequency, frequency band should be the same

Answer:  All frequency bands are tuned to the same shape. Please refer to the Figure 2, Figure 3, and Figure 5.

Comments 1:

• Line 24: The insertion and return losses of the first frequency passband (fo1) are 0.09à is it dB or just the number.
• Line 27:  The insertion and return losses of the second frequency passband (f02) are 0.21 à is it dB or just the number
• In general, both must be very low (0) at this frequency of operation

Answers:  

Theoretically, the insertion loss should be zero and the return loss should be infinite. However, because of material loss and metal loss in the filter, insertion loss cannot be zero and the closer to zero the better. Also, the return loss cannot be infinite because of the material and metal losses of the filter, the higher the dB value (-dB) the better. I re-simulated the filter and re-measured it. I tried to get a value with an insertion loss close to zero and a high return loss due to my efforts.

Comments 1: Line 52: The SIR structure is expressed as open stubs with low and high impedances. --> you need a very clear clarification why as such

Answers: I added the sentence corresponding to the SIR definition (Z_A and Z_B).  Please refer to word lines of 111 to 117 and reference of [17]-[19].

Comments 1: Line 123: you are comparing 2.8 GHz with 2.85 GHz and showing the same bandwidth.  Ideally, the frequency band the center frequency should be the same. That needs to be corrected.

Answers: Theoretically, the simulation result and the measurement result should be the same. However, due to the internal mechanical loss of the measuring equipment, the measurement results cannot match the simulation results. Therefore, it is known that the error of the measurement result is acceptable within 5%. And the measurement was repeated so that the measurement result could be reached within 5%.

Best of luck, hope to see the improved version. 

Thank you!

 

Answer :

Thank you again for your interest in my paper.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Thanks for applying the comments.

I also have a suggestion for you to add much more value to the present version of the paper. You may also call another application of your proposed design as a sensor rather than a filter since there are quite a few sensitive gaps in your design which are naturally susceptible to environmental dielectric changes. This can be viewed as a change in the frequency of one of your passbands' central frequency. You may consult following literature to add a paragraph as a future application (using which is at discretion of authors)

10.1109/TMTT.2018.2791942

10.1109/TMTT.2021.3081119

 

 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf