How to analyze the balanced microstrip?

[fishyxl]

Right now in my research work, I have encountered a new transmission line----the balanced microstrip in a printed linear antenna and in a tapered slot antenna. I wonder if anyone can give me some advice on how to analyze such a transmission line. Thank you!

 

[flyhigh]

Hi,

first, lets define what balanced microstrip is. To the best of my knowledge, it is the structure consisting of two strips equal in width placed one on top of the dielectric substrate, the other on the botom (no ground plane).

One can insert a virtual ground plane in a symmetry plane of the dielectric substrate. The one strip is then the electrical image of the other one. Having this in mind, one can derive the characteristics of balanced microstrip based on analysis of the clasical one. The effective dielectric constant will be the same for both of the structures. The characteristic impedance of the balanced microstrip will be twice the impedance of the classic structure as the voltage between the balanced conductors is twice the voltage of the classic structure and the currents are the same.

Hope this helps

flyhigh