hi guys! I'm new to the group and new to designing for high frequencies. My problem is I'm confused with Coplanar Strip Line. Is it in the family of Strip Line or Coplanar Waveguide? Pls help! Thanks!
Stripline TL have a microstrip that is sandwiched between a ground plane above and below...it can be symmetric or asymmetric
Coplanar Waveguides have a microstrip line that has two ground planes on either side that are coplanar with the microstrip.
Coplanar Striplines are simply the superposition of these two. So it is a microstrip line that has two grounds planes on either side that are coplanar and this plane is sandwiched between two ground planes above and below (separated by a dielectric of course) You can occasionally see these TL in PCB boards in the internal layers.
The advantage of coplanar is that parts can be soldered in shunt directly between the two conductors. This eliminates the parasitic inductance of a via and the parasitic capacitance of a soldering pad. These can be major problems in the microwave region.