How to design coaxial feed for fractal microstrip antenna using CST (Need Help)

[vadhil]

Hi.. I'm newbie here,
I would like to re-design fractal microstrip patch antenna for my final year project from the attachment file. but i dont know how to design the coaxial feed for it antenna in cst. How should i define the port at the feed point.
i'm using cst software to design. Thanks A Lot..

View attachment Ultra Wideband Fractal Microstrip Antenna - Azari & Rohwani.pdf

 

[arxlan]

Hey vadhil,

In order to design the coaxial feed you first need to substract a circle of 2mm from the substrate at the point where you need to place ur feed.
Then using cylinder to fit in the substratced place by giving it height in -z as your substrate is laying on 0. After this you need to design two pins
of diameter 1.6mm i.e by using cylinder placing the pins inside the above cylinder i.e starting from -z upto the substrate height and then second pin from substrate height upto the patch.
Assign vaccum to the cylinder with 2mm of diameter and assign PEC to the pins.

 

[vadhil]

hi arxlan..
thanks a lot for your answer.
its very helpfull.

but, I still confuse about the pin.. can u show me in a picture or you can draw how pin look like..
I'm so sorry for disturbing you..

thanks before.

 

[arxlan]

Attached are the pictures of coaxial feed.



Now you can easily understand about the inner pins and the outer conductor and i already told you the diameters. Just make sure before starting
you need to subtract a circle from the substrate with diameter=diameter of external cylinder.

For the excitation you need to draw a circle at the bottom of the external cylinder and then assign waveport to it, like this:



Now just try to make it according to this procedure and hopefully you will get your results.
If you got any problem, you can ask me.


Regards,
Arslan.

 

[vadhil]

dear arslan..
thanks for your guide. I tried to design according to your design, but i didn't get the result, there is still an errors..
maybe you can check my design for the errors.
thanks

here is the design attachment :
View attachment fractalantenna_3.rar

 

[arxlan]

I have seen your design, probe feed is not correctly defined. I will try to check it back again and will provide you by
correcting it.

Regards,
Arslan

 

[vadhil]

thanks arslan.

I will wait for the correction.