U-slot antenna

[Admin 2545]

,,, type of antenna,not very easy to produce , but with good results in circular polarization.
Between the patch and  irradiated put plate of polystyrene or polyurethane...

 

[sandeepv 10]

how to know whether it is LHCP or RHCP  ?

[Admin 2545]

,,,unless if you translated feed point to the left or to the right...!!!

You can try...!!!!

[MrElec 0]

For circularly polarization, can you offer axial ratio vs frequency and the method to obtain this result.

[Admin 2545]

10 hours ago, MrElec said:

For circularly polarization, can you offer axial ratio vs frequency and the method to obtain this result.

This is what you want?

 

[MrElec 0]

In fact i want to knowhow to plot Axial Ratio of a circularly polarized antenna Vs frequency (tha gragh is a cartesian one AR =f(frequency) ). I tried your model but i can't get the same results. I've attached the project. So could you tell me please what was wrong with the model and how to deal with the AR.

U-Slot Patch Antenna.cst

[Admin 2545]

what kind of dielectric spacer did you choose?
with what dielectric constant(relative permittivity)?

the best is polystyrene,,,!!!

[MrElec 0]

Hi,

I worked with foam loaded from CST material library. The relative permittivity of the dielectric is 2.2.

 

[Admin 2545]

what kind of material?

[MrElec 0]

Oh no, excuse me Admin i have made a mistake. In fact, i've created this material and renamed it to foam. 

[MrElec 0]

So what dielectric did you used for the antenna ?

[Admin 2545]

,,,create another type of material (polystyrene) in CST material library, with er=1,2 and load it...!!!

[MrElec 0]

This is what i've obtained :

[MrElec 0]

Do you have a reference to this antenna ? Also, may be the meshing is not good.

 

[Admin 2545]

1 hour ago, MrElec said:

In fact i want to knowhow to plot Axial Ratio of a circularly polarized antenna Vs frequency (tha gragh is a cartesian one AR =f(frequency) ). I tried your model but i can't get the same results. I've attached the project. So could you tell me please what was wrong with the model and how to deal with the AR.

U-Slot Patch Antenna.cst

your CST file I can not open ?!

 

 

My *cst file,,,!!!

 

E-Patch.cst

[MrElec 0]

I'm using CST MWS 2017. 've opened your project and now i see my problem. I've used PEC sheets and the dimensions are not the same. This is why we got different results. Now for circular polarization, usually we demand to plot axial ratio versus frequency in cartisian system AR = f (frequency) to prove that the antenna is circularly polarized. I think that there are some changes in the far field propreties. What do u think ?

 

[MrElec 0]

Did u measured the S11 parameter and the radiation diagram ?

[MrElec 0]

result of simulation of your project :

 

[Admin 2545]

I did this simulation today and I did not have time to optimize something ... !!!

to me that looks,,,!!!!

[MrElec 0]

Yeh, your project gave S11 = -14.09 dB but it's value -42.37 dB in your first post. 

[Admin 2545]

 in the past I think I used another dielectric with other dimensions

[MrElec 0]

Do you have a reference for this antenna ?

[Admin 2545]

3 hours ago, MrElec said:

Do you have a reference for this antenna ?

not

[MrElec 0]

Ok thank you

[sandeepv 10]

in order to get the circular polarization you can vary the two side arm lengths of the U slot.....there are pretty good papers in IEEE explaining the CP generation using U slot....but you wiull get narrow Axial ration bandwidth in such cases.....in order to get wider axial ration bandwidth go for slot antennas.