CPWG transmission line impedance
Domagoj , 09-12-2023, 09:34 AM
Has anyone encountered an impedance variation of a coplanar waveguide with ground plane similar to this one on the image?It is a 4L PCB with CPWG on L1, reference plane on L2, h = 0.148 mm, w = 0.25 mm, g = 0.2 mm, Dk = 4.6.I can't explain the sudden jump in impedance from ~30ohms at around 2.2 GHz to ~60ohms, and then it stays at that higher value.
QDrives , 09-12-2023, 08:25 PM
Is this a:- measurement- simulation using 3D field solver- calculation tool- other?
Domagoj , 09-14-2023, 06:33 AM
Measurement, i.e. calculated from S-parameters by using the lossy transmission line model.The calculation was confirmed using a known good through line on a different PCB.
Domagoj , 09-14-2023, 06:35 AM
And also confirmed on two frequencies using this method https://hamwaves.com/zc.measuring/en/index.html
Robert Feranec , 09-21-2023, 12:08 PM
was the cable calibrated correctly?
Domagoj , 09-21-2023, 01:52 PM
Yes, OSLT calibration was executed.
Use our interactive Discord forum to reply or ask new questions.