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How to design a impedance matching network ?

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fishyxl

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broadband matching: theory and implementations

My boss asked me to design a impedance matching network , but I am at a loss how to handle it . Can anyone give me some instructions or references? Thank you. The parameters are as follows:

f1=1890MHz Z1=27.8+j8.9 (L=700PH)
f2=1900MHz Z2=28.5+j10 (L=855PH)
f3=1910MHz Z3=27+j12 (L=1.04nH)
f4=1920MHz Z4=29.3+j14.4 (L=1.13nH)

The VSWR needs to be lower than 1.2
 

flatulent

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If you want quick results, Nuhertz Z match has a 20 day free trial period. It gives LC and transmission line networks.

One simple solution is to put a capacitor in series with the load that removes most of the reactance and use a quarter wave line of impedance around 35 ohms. This will get you close but possibly not under the 1.2 SWR figure you need.
 

yorande

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You have to deal with impedance matching in different frequency at the same time?? Sounds strange.
For reference, I think Chris Bowick'S "RF CIRCUIT DESIGN" is good.
 

vagarwal

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to me it appears to be a broadband match kind of thing... the BW is 30 MHz and the impedances are also in close vicinity... but then for such an approximate match, a VSWR of 1.2 is doubtful...
 

springf2000

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use the smith tool for impedance and then use the ADS to simulate and tunner, you can quickly get your impedance matched network!
 

khouly

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reffer to gonzalez book in chapter 2 see the techniques used for matching network design using smith chart it is simple

then use any tool u can have like smith tool to design the matching circuit

wish this help

khouly
 

No one

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Hello;
I advise you to see the following books:
- Microwave engineering, Pozar
- Foundations of Microwave engineering, Collin
- Microwave Transistor Amplifiers, Gonzalez
Also I advise you to use one of Microwave related softwares like MWOffice, ADS, ....
 

jallem

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It looks like a broadband matching network.
You have two options: Matching at the center
frequency of the band(very simple, use winsmith
or read Gonzalez book, cap. 2) or match the
whole band. In the last case I recommend the book:
BROADBAND MATCHING: THEORY AND IMPLEMENTATIONS
(2nd Edition) by W-K Chen (Univ. Illinois, Chicago),
ISBN 9971-50-219-4. However, be aware that broad band
matching can lead to instability and maybe loss. In other
words ther is trade off. For other hand, I dont think your
boss is asking for broadband matching.
 

fengjian

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the passive circuit match in ADS
 

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