Energy issues and warnings using caoxial port

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nikthegreek
Posts: 5
Joined: Sat 27 Apr 2019, 10:54

Energy issues and warnings using caoxial port

Post by nikthegreek » Fri 04 Oct 2019, 08:55

Hello,

i am trying to create 8 SIW monopoles for 5G communications and i am using coaxial ports.Although,i created the mesh so that it "catches" the probes(i used DetectEdges as well insted of my lines) i still get this warning:

Warning: Unused primitive (type: CylindricalShell) detected in property: probe!

for every probe.My resoluton is at λ/20.When i changed it to λ/40 without DetecgtEdges or my additional lines this warning appeared 6 times and not 8 as before.Why is this happening?

My second issue is my energy.I cannot reach -50dB.It stops around a value higher that.I used a PML with 8 cells on the one end of the coaxial port.It seems that the energy is captured inside the PML.I don't know how to solve this issue.Am i feeding the PML the way i created the port?

I post my code for further detail!

Thanks in advance
Nick
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monopoles5G.m
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PaulUK
Posts: 81
Joined: Wed 28 Oct 2015, 14:23

Re: Energy issues and warnings using caoxial port

Post by PaulUK » Fri 04 Oct 2019, 13:34

I just deleted a reply because I misread your boundary conditions. Have you tried to cap the ends of the coax with a PEC cylinder? Im taking a look at your model and if I can figure out the problem I'll post later.

thorsten
Posts: 1438
Joined: Mon 27 Jun 2011, 12:26

Re: Energy issues and warnings using caoxial port

Post by thorsten » Fri 04 Oct 2019, 13:41

You outer coax shells are way to thin. Mesh lines will never really hit them, make these walls much thicker.
Currently you coax do not have any outer conductor! openEMS does unfortunately not model curved thin metals very well... We would need a conductive surface model...
Use RunOpenEMS with the "--debug-PEC" to find such problems more quickly...

regards
Thorsten

PaulUK
Posts: 81
Joined: Wed 28 Oct 2015, 14:23

Re: Energy issues and warnings using caoxial port

Post by PaulUK » Fri 04 Oct 2019, 14:07

Can a PEC end cap be used at the end of a coax transmission line and have the port at the coax-PEC endcap plane, in a similar way as can be done with waveguide?

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