Airbridges in CPWs

Hi Guys!
do you know at which distance from a transition (i.e. a bend) it is worth to place airbridges?
I have to design a CPW for 0-7GHz application using two metal layers and this CPW must have a 90° bend.
Thanks for the help

Leron

Hi,

just a rough advice, not a very exact one. You place air bridges in CPW to disable the propagation of coupled slot mode. It is excited on any discontinuity/unsymmetry of the line. Thus, it is best to place bridges on both sides of the 90deg bend as close to the bend as possible.

One more thing, if your line is long in either direction from the bend, use more than one bridge. The distance between the bridges should be less than quarter wavelength on highest frequency of the band.

flyhigh