influence of CPW substrate thickness on CPW loss
I read from some paper that say the h should be larger thant W+2S to reduce the interactive between surface wave mode and CPW mode.
But on the other hand the h should be smaller than the 0.1 lambda (in substrate) to increase the cut-off frequency of surface wave model.
Can somebody explain a little bit to me.
Thanks a lot
Hello,
I know the following articles talk about this topic, go through them...
[1]Effect of substrate thickness and metallization thickness on dispersion characteristics of CPW
by A. K. Rastogi, N. J. McEwan, I. U. Khairuddin and A. Z. Jakal
SpringerLink - International Journal of Infrared and Millimeter Waves, Volume 16, Number 8
[2]Substrate loss mechanisms for microstrip and CPW transmission lines on lossy silicon wafers
by Dimitri Lederer, and Jean-Pierre Raskin
I don't have copies of the above documents, & hence you need to search...
Alos try AWR Txline- Afree Transmission line Calculator which helps quickly understand CPW parameters...
http://web.awrcorp.com/content/Downloads/TXLine.zip
---manju---
Hey,
Try using Linecalc in ADS and you can observe the effect of di-electric thickness (h). I used for one my applications. But I am not sure about your concern regarding the cut-off frequency of the SWM.
Can you please elaborate.
Thank you
Samkeet
In CPW in order to concentrate the fields in the substrate area and to minimize radiation, the dielectric substrate thickness is usually set equal to about twice the gap width.