find focal point

Hi.

I′m simulating a offset dish, i was wondering if CST is capable of calculating the focal point of the antenna?

Using CST 2006.

Best Regards.

ok suced
assume u have horn as feeder,ok
as u make offset reflector,u ask about where i could set the feeder.that is ur question?
if yes it so easy,in cst after u simulate the feeder alone,in farfield pattern calculation ,choose phase center in its option
u will see the location from the feeder port where u should locate the feeder above the focal length of the dish
at all,could pls upload ur design here
regards

I have a conical horn placed in the theorically focal point of the offset dish and i understand that the conical horn phase center should match the reflector focal point..

..but supposing that we dont have the math′s to calculate a offset dish focal point, is there any way to CST calculate that? (just the focal point, no conical horn angles)

testing one mm at each time with 12 million of mesh cells..it′s a lot of time....

How about using Grasp to design the reflector ?
Its a software for designing reflector antennas.

suced,again could upload ur design,may we could help u

The software belong to the company that i work, i dont have the authorization to do that..


We usually dont work with reflector antennas..but if Grasp have that possibility to calculate focal point′s, i will have a look.

Most of the time, for grasp, the focal point is define at the design stage (at least that what i do most of the time)

But it also use GO to plot out the ray paths. Maybe this can help to estimate the focal point. I'm not sure about this.

But Grasp is freeware or shareware?

My thought in CST...

-First i calculate the phase center of the Horn (alone)
-Second i calculate the phase center of a parabolic dish (normal, not offset...alone, with no horn feed), using a discret port

Subtract both phase center′s and place there the Horn..

Only tomorrow i can test this...

suced.here we discuss our problems ,so we could help if u just upload ur file of cst.we all here have cst2008 like u
don't be fair,we just help
regards

I dont have any version of CST in my pc. If i could and even if i had CST in my pc, what′s was the problem of upload it? it just an offset dish antenna with a conical horn..no secret here. But i′m just a trainee in the company, i dont want any problems.

i hope you understand..sorry.

no problems.no sorry,as u like

There is a free student version.