coplanar strips

Hello RF- and MW- experts,

I have so problems with ADS 2006A / Ansoft Designer and I hope that you can help me. Before I describe my problem, I want to say, that I'm still learning these softwares.
My problem is that I want to design coupled differential pairs circuits, also known as coplanar strips circuits) on a InP chip in a Frequency range between 100-300 GHz. Unfortunally I cannot find the right ADS or Ansoft Designer librarys for coupled differential pairs without ground plate / coplanar strips.

So my questions are:

Are there any coplanar strip librarys for these two softwares ?
or do you know any trick to develop a coplanar strip from other librarys ?
or must I calculated all the circuits with ADS Momentum / HFSS.

Thanks for your help

Best regards
DSHHI

You do not find the components in library.
You need to do it in Momentum, HFSS or any EM simulator.