Click here to go to our main page on coupled line couplers
Click here to learn about Henrik Forstén's on-line 2D EM field solver tool
Click here to go to a page on a PolyStrata 10 dB coupler design analyzed with an Henrik Forstén's on-line EM tool
Click here to learn about the PolyStrata process
Click here to see a GaAs microstrip10dB coupler analyzed with Henrik Forstén's tool
New for February 2026. The PolyStrata process is available exclusively at Nuvotronics, unless you work in China and managed to steal their intellectual property. It is used to make 2.5D structures, notably air-dilectic recantangular coax. Unfortunately, linear EDM tools such as Microwace Office don't possess a linear model rectangular coax, and if you want any accuracy at all you need to use expensive tools such as HFSS or CST. One this page we will show you how to model PolyStrata coax accuratly using an on-line 2D EM tool.
https://hforsten.com/field_solver.html
Data for a a 700um tall PolyStrata 50 ohm line is stored here Here's a view of teh cross section.
Here is the impedance that was calculated. Note that the solution does show the effects of skin depth on impedance at low frequency. This is a real thing, but it can usually be ignored.
Here are S-parameters for a 100mm line. You can download teh S-parameters, or just point to any point on the line to read the daya.
Here is a 10dB coupler design