How to design a 50ohm microstrip line that works on 900, 1800, 2100 and 2500 Mhz?

Hi to all!
Can anyone tell me how to design a 50ohm microstrip line that work on 900Mhz, 1800Mhz, 2100Mhz, 2500 Mhz?
I have to built in on FR4 (epsr=4.4 tangentloss=0.02 1.6mm thikness) to feed a monopole slot antenna.
I try to use Txline software but it does not give a good width, I need some formulas if anyone know.

thanks to all

Francesco

You tried to lineGuage professional.

You need to make the line width 3.06 mm or 120 mil.

i'm sorry.Above picture is wrong.

This picture is true.

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Are there any formulas for the same?

Also, can anyone direct me to a quarter-wavelength microstrip calculator to match the microstrip feed and the patch. How do you get the length and width for a particular frequency?

Agilent has a free one: AppCAD. There are others around. The best of the lot is Polar Instruments but it is not free.

Added after 1 minutes:

Now that I think about it, I probably should not have said "best" as that will spark a discussion of 17 alternatives that are better.

Polar's is just another choice.

Appcad download link

http://www.hp.woodshot.com/appcad/appcad.htm

please refer Ramesh garg : Handbook of Microstrip antenna .. u will find all the formulas there ..

If I should use the microstrip line to feed a multiple band antenna which freqency I should consider to adapt it?
Example:

antenna for GSM/DCS/UMTS 900Mhz, 1.8Ghz, 2.1 Ghz which one to choose for dimension of microstrip line?

thanks

Francesco

When you design transmission line (TL) frequency is not in the equations for geometry, only for losses. Good TL does not depends on frequency unless you specifically need to get some length (quoter wave or certain length for resonator, etc). The best inexpensive TL design tool is TL calculator in LINC2 RF design program. It provides the same accuracy as expensive but very good Polar. LINC2 just easier to use than Polar, but it is numerical calculator whereas Polar is field solver.

BR,
RF-OM

Thanks guys.

But the link for download link for AppCad doesn't work. Is there any other software tool?

Added after 5 minutes:

I'm answering my own question here. I found another link for Appcad. Hope it helps.

http://www.rfglobalnet.com/download....=1214569489071

Be careful with this program. It is free and the accuracy is not very high. It is okay for student projects but you may be frustrated if you use it for real project.

Br,
RF-OM

I agree with RF-OM. Its not a 100% accurate.. Maybe thats why its free. Its good enough for student projects. However, it would be best to cross-check the results in HFSS too.

HFSS is a good tool when you need to simulate TL with other stuff. When you try to simulate TL alone you need to include all the data about walls, distances and so on. In time of initial TL design you often do not have all this data and it makes HFSS usage questionable. Personally I prefer to use my own worksheets that I prepared for design and then check result with LINC2 TL calculator. I trust it. Polar is also very good TL calculator (field solver) and can be used with trust, but it is slower and expensive. This two stage TL design method is well proven and save time.

By the way, LINC2 also is very good for yield prediction. Statistical analyzes are easy and fast with tis program as well as optimization when it is necessary.