How to calculate the width of transmission lines for matching?

Hello everyone,

I am trying to make a single diode harmonic mixer with a RF matching network at the input (5.25GHz) and IF matching network at the output (10.5GHz). I am trying to use transmission lines and stubs in a substrate of Er = 2.2. How do I calculate the width of the lines?

Should I match at one frequency or my approach is correct?

Thanks

go here for microstrip lines and their impedance calculations

http://www.microwaves101.com/encyclopedia/calmstrip.cfm


cheers
Dave
VK2TDN

Thank you

TX Line, the free transmission line calculator from AWR is one of the most useful tool.

http://web.awrcorp.com/content/Downloads/TXLine.zip

you can also consider AppCad (freeware available everywhere) passive circuits tools for this.

you can also use this tool if you want create a lumped matching:

http://www.uwaverf.altervista.org/in...temid=54#match

First all thank out everyone for your replies. Secondly, my design has patch antennas operating at 5.25 GHz and 10.5GHz, there dimensions are very small. If I use the above calculators, I am getting the width of transmission line around 4.9 mm, which is comparable to my patch dimensions. When I take arbitrary width of 0.02mm I get the following results. Does that mean that my circuit is matched close at 50 Ohm?

The figure shows S11 and S22

What I mean is I am using the width of the transmission line to match my real part of the impedance and length for matching the inductance. Is it oky? I am getting correct simulation results. Will this approach have any problems in the manufactured design?