How to design branch line coupler in HFSS?
Can any one help em how to design a Brnach line couple I'm totally new to HFSS, I check the help fine and also few examples I designed a patch Antenna also but I'm not sure how to start for Branch line coupler.....
Hello gvinu4u,
For Branchline coupler it is always better to start with Circuit Design tools initial design & optimization & then simulating in Electromagnetic tools for accurate simulation...
I recommend AWR Microwave Office (MWO) which has good Microstrip/Stripline models library & integrated layout editor...which also has integreted em simulator for accurate analysis of passives...
Here is the document/article on Brachline coupler design procedure using MWO...
http://www.acsu.buffalo.edu/~eastman2/report2.pdf
Also you can use other Circuit tools from Agilent ADS or Ansoft Designer, APLAC or Genesys,etc..
---manju---
I got with the basics but in designing the Branch Line Coupler, I am not able to find the formula for the width of the Branch Line coupler. The length is lambda/4 as usual. I'm using Ansoft HFSS V10. I need the formula for the width of the strip.
@gvinu4u:
Because you got the basic principles of Branch line coupler, So I guess you also calculated characteristic impedance for each branch.
To calculate Microstrip line width from a given characteristic impedance, find a tool which names "txline" on internet, it can be freely downloaded. By using this tool you can calculate all of parameters of your transmission line.
Next step will be simple with HFSS v10.
do not hesitate if you have any question!
cheers!
the design of the branchline coupler is simple you need first read same theory about it. You also need tools like Txline (free) or linecalc ads (not free) then it is easy to have the dimenssion of your coupler with it.
than use hfss to buid your coupler and to simulate it .