Antenna Matching
I am trying to get an optimum match for my planar antenna by altering the model. I am trying to do this by looking at the E-Field Monitor. Since I am new to this topic, can somebody explain how to do this the best way. I mean how to know where the highest reflection is. I am using CST-MWS.
Really appreciate your help. Thanks in advance.
Regards,
abti
You would be better off checking the S-parameter S11 for a tuning problem, or the smith chart, just ensure you know what impedance you are referencing to.
Matt
there are two problems:
1-tuning
2-matching
firstly you should change parameters and observe S11. note which parameters increase resonance frequency. I use linear magnitude of S11.
having obtained correct freq., you should match the antenna. for this part, I use smith chart. change other parameters to get 50 ohm impedance.
I have not studied on planar antennas, so I do not know which parameter changes freq. If different parameters change either resonance freq. or matching condition, it is good.
hope this helps.
Hi abti,
What type of planar antenna are you looking at ? If it is a microstrip patch antenna with microstrip feed on the same substrate, then you should look at varying the inset position and adjusting for lowest possible S11. Similar thing holds for a probe fed patch antenna where you need to adjust the probe postion.
You can define some variables for these lengths and use either a parametric sweep or the optimizer.
-svarun
Thank you all for your kind help.
Answering svarun:
I am working with a three-offsets planar antenna fed by CPW. It looks something like a T-shape antenna with 2 stubs connected to it.
Regards,
abti
Use ferrite balun, transmission line in your planar.
hi
for overcome for this problem you can either change position of stubs and either position of antenna feed.