Design and Implementation of Low Parasitic Inductance Bias Circuit for High-Power Pulsed Power Amplifiers
, Wenrao Fang 2,*, Ruyu Fan 1, Lulu Wang 2, Wenhua Huang 2, Yuchuan Zhang 2 and Changkun Liu 2
Zuo-Min Tsai
Round 1
Reviewer 1 Report
This manuscript includes an interesting design for a power amplifier biasing circuit by using shorter transmission lines and wider series transmission lines. The manuscript includes the idea, circuit analysis, and measurements. There are some questions.
* In the design, Zb is set to 200 Ohm. However, for the material er= 2.2, thickness = 0.508 mm. The width of the 200 Ohm line is roughly to be narrower than 0.1mm. This is not consistent with the photo in Fig. 11b. This is suggested to verify the line impedance and the line width.
* It is suggested to add the performance of the power amplifier (S-parameters, Pin vs Pout) with the proposed biasing network and the traditional biasing network.
Author Response
Point 1: In the design, Zb is set to 200 Ohm. However, for the material er= 2.2, thickness = 0.508 mm. The width of the 200 Ohm line is roughly to be narrower than 0.1mm. This is not consistent with the photo in Fig. 11b. This is suggested to verify the line impedance and the line width.
Response 1: Thank you very much for your question. Because Zb is twice that of the bias line's characteristic impedance, so the bias line's characteristic impedance is 100 Ohm, not 200 Ohm.
Point 2: It is suggested to add the performance of the power amplifier (S-parameters, Pin vs Pout) with the proposed biasing network and the traditional biasing network.
Response 2: For high-power power amplifier, its S parameter is not generally tested because of the obvious difference between its output microwave and the state when it does not output microwave. Normalized input and output power of the traditional and proposed power amplifier systems are now added to the revised paper, please check it.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The first sentence of the introduction paragraph - “…two types CW power amplifiers…”: why in not mentioned in brackets what it means the CW abbreviation?
The literature review (with the mentioned references) looks too short in the introduction paragraph and do not present an exhaustive review of the actual stage in the discussed scientific topic.
Fig_1: it is expressed the relationship between the drain current/voltage, and input/output power. How can the authors prove (argue) the waveforms shown in figure?
Fig_1: usually in journal paper publications the figure text and labels should be with similar size as used in the text body;
Equation_1: similar observation as above;
Text body: why are not edited standard indexes for the used magnitudes (Vds, Ids, Pin, Pout, etc.)?
Fig. 2,3,7: similar observations regarding the text and labels as for Fig. 1.
The full text body: why are not edited standard indexes, as it is for example in Equation 2?
The waveforms thickness (red and blue) in figures 8 and 12 looks oversized (more adequate are sized in figures 5, and 6.).
In a journal paper publication a figure is never followed directly by a paragraph title (as fig. 15). Usually some body text (explications, description, etc.) is inserted between the two.
The references list looks a little bit poor for the mentioned topic.
Strictly from scientific point of view the paper looks meritorious.
Unfortunately, it is prepared with several edition and presentation errors, as has been remarked above.
After a major revision process the paper may become suitable for journal paper publication.
Author Response
Point 1: The first sentence of the introduction paragraph - “…two types CW power amplifiers…”: why in not mentioned in brackets what it means the CW abbreviation?
Response 1: Thank you very much for your question. I added an explanation in the modified version, please check it.
Point 2: The literature review (with the mentioned references) looks too short in the introduction paragraph and do not present an exhaustive review of the actual stage in the discussed scientific topic.
Response 2: I revised the literature review and introduction, please check it.
Point 3: Fig_1: it is expressed the relationship between the drain current/voltage, and input/output power. How can the authors prove (argue) the waveforms shown in figure?.
Response 3: The relationship between drain current/voltage and input/output power is referenced from the literature, which I quoted in the revised version.
Point 4: Fig_1: usually in journal paper publications the figure text and labels should be with similar size as used in the text body;
Response 4: I corrected it in the revised version, please check it.
Point 5: Equation_1: similar observation as above;
Response 5: I corrected it in the revised version, please check it.
Point 6: Text body: why are not edited standard indexes for the used magnitudes (Vds, Ids, Pin, Pout, etc.)?
Response 6: I corrected it in the revised version, please check it.
Point 7: Fig. 2,3,7: similar observations regarding the text and labels as for Fig. 1.
Response 7: I corrected it in the revised version, please check it.
Point 8: The full text body: why are not edited standard indexes, as it is for example in Equation 2?
Response 8: I corrected it in the revised version, please check it.
Point 9: The waveforms thickness (red and blue) in figures 8 and 12 looks oversized (more adequate are sized in figures 5, and 6.).
Response 9: I corrected it in the revised version, please check it.
Point 10: In a journal paper publication a figure is never followed directly by a paragraph title (as fig. 15). Usually some body text (explications, description, etc.) is inserted between the two..
Response 10: I corrected it in the revised version, please check it.
Point 11: The references list looks a little bit poor for the mentioned topic.
Response 11: I added some references, thank you for reminding
Author Response File: Author Response.pdf
Reviewer 3 Report
Dear Respected Authors,
I have found your paper very interesting. The topic is significant to anyone who is involved in designing the power amplifiers.
The paper contains several things to improve and I recommend to check and correct them:
1. Fig. 11 - it seems that the pictures are on wrong places - a) is proposed and b) is traditional.
2. Line 47 - the drain current should be changed from Id to Iq ? See the equation below. Or in the sentence should be "turned on".
3. Please specify which kind of class is your amplifier ?
4. Fig. 2. Please describe in the text what is the value of gate-source voltage, if you change it ? Why the bias voltage at drain is pulsed - do you switch the gate-source voltage or drain-source voltage ?
5. References:
position 2: there is the text to remove: Author 1, A.; Author 2, B etc.
position 3: there is a number 5 and no journal or conference
Best regards
Author Response
Point 1: Fig. 11 - it seems that the pictures are on wrong places - a) is proposed and b) is traditional.
Response 1: I corrected it in the revised version, please check it.
Point 2: Line 47 - the drain current should be changed from Id to Iq ? See the equation below. Or in the sentence should be "turned on".
Response 2: The drain current should be changed from Id to Iq. I corrected it in the revised version, please check it.
Point 3: Please specify which kind of class is your amplifier ?.
Response 3: The class of the power amplifier is AB. I made it clear in the revised version
Point 4: Fig. 2. Please describe in the text what is the value of gate-source voltage, if you change it ? Why the bias voltage at drain is pulsed - do you switch the gate-source voltage or drain-source voltage ?
Response 4: The gate voltage is negative and continuous.I switch the drain-source voltage.I made it clear in the revised version
Point 5: References:
position 2: there is the text to remove: Author 1, A.; Author 2, B etc.
position 3: there is a number 5 and no journal or conference
Response 5: I corrected it in the revised version, please check it.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Thanks for the replies.
For the performance of the power amplifier. It is suggested to give the dBm value of the Pin and Pout rather than the normalized results.
Author Response
Thank you very much for your suggestion. I need to explain that due to the need of confidentiality, my research institution does not allow the disclosure of the specific value of the dBm value of the Pin and Pout, so I must use the normalized result. The dBm value of the Pout is about 66dBm, but it cannot be stated in the article. I can only write in the article that the normalized power standard is kW level. I hope you can understand and allow it. Thanks again!
Reviewer 2 Report
The manuscript has been sufficiently improved to warrant publication in Electronics.
Author Response
Thank you very much for your recognition. Your help makes the article more perfect. Thank you again!
Author Response File: Author Response.pdf
