Learning Forum

[yank4]

I want to measure the E field transmitted from the bottom of the box to top of the box. I assigned floquetport1 on the bottom face of the air box and floquetport2 on the top face of the air box. The problem is I keep getting reflection from far field report. 

The reason I think the report is giving me reflection is because of the following reasoning:

First I send excite the empty box from port1 to port2

The result is as follows

Phi is 0. And I put the marker at point Theta = 0 to see the Etotal at the direction of the z axis. (in the graph I picked three frequencies so I got three lines)

Then I put the pec to the air box to try to block the signal.

And get the far field report same as previous

Compare the data when theta= 0, phi = 0, we can see when the air box is empty, the data is small. When the air box is blocked by pec, we can see the data is large.

Which seems to imply that the report shows the value of the reflection. As the empty box do not reflect signal. And the pec reflect large amount of the signal. 

Finally, as I stated in the beginning, I want to see the data of the transmission from port1 to port2 instead the reflection at port1. Is there anyway to change the settings? 

Thank you so much!!!

[asamaiyar]

Hi yank4,

How are you getting far fields? Do you have a radiation boundary (or FE-BI or PML)? If yes, where is it?

--AS

[yank4]

Hi Asamaiyar,

I used pairs of master and slave boundary conditions around the 4 sides of the air box as floquet port required.

Thanks!

[asamaiyar]

Hi yank4,

HFSS cannot generate rETotal, or rELHCP, or rERHCP without a radiation (or FE-BI, or PML) boundary. Please check your design. There is some kind of radiation boundary in your model.

Thanks,

AS

[yank4]

Hi asamaiyar,

I thought the master and slave boundary condition is radiation boundary for the rEtotal etc because it is a floquet port?

I see how to use floquet port from http://www.1cae.com/articleAccessory/2017/04/16/HFSS%20Floquet%20Ports.pdf they just set the master and slave boundary. 

Thanks!

yank4

[asamaiyar]

Hi yank4,

I stand corrected. Far fields can be obtained from your configuration.

Back to your issue.

I don't know how the radiation is calculated from floquet ports and master-slave boundaries so I would suggest using S-Parameters to check how much transmission is happening from port1 to port2. In this way you can also calculate the transmissions to the mode level.

Few other debug ideas for far fields (I am not sure if they will work):

1. Check the coordinate system to which your Infinite Sphere is aligned to

2. Check which mode is excited using "Edit Sources.." option

Thanks,

AS

[yank4]

Hi asamaiyar,

I will look into that. Thank you!