GEOMETRY
Newbie level 5
Hi,
i am trying to capacitevely couple the maximum of power from a first microstrip line to a second one.these lines are not parallel so they do not lie on the same substrate (picture below).
These 2 lines have special geometry and are separated from each other by an airgap.
Each transmission line is constituted by discontinuous conductors disposed on opposit sides of the substrate layer.(picture below)
A second substrate separe Each line and the aluminium ground.
Each line has 2 ports:
- port 1 and Port 2 are related to the first line.
- Port 3 and Port 4 are related to the second line.
Before coupling the 2 lines, i succeeded to obtain an S21= -0.1 dB ( for the first line) and an S43=-0.10 dB (for the second line) which are very good.
The problem is that when i tried to couple the lines, my maximum S31 or S41 is - 4.9 dB which is not good at all :-( , since i am trying to couple all the power from the forst line to the second (-1dB<S31 & S41<0 dB)
What are the boundaries to use?
Can you help me please to have an S31 or an S41 less than -1.5 dB :roll:?
https://obrazki.elektroda.pl/18_1332170289.png
https://obrazki.elektroda.pl/90_1332170338.png
https://obrazki.elektroda.pl/5_1332170357.png
https://obrazki.elektroda.pl/38_1332170374.png
i am trying to capacitevely couple the maximum of power from a first microstrip line to a second one.these lines are not parallel so they do not lie on the same substrate (picture below).
These 2 lines have special geometry and are separated from each other by an airgap.
Each transmission line is constituted by discontinuous conductors disposed on opposit sides of the substrate layer.(picture below)
A second substrate separe Each line and the aluminium ground.
Each line has 2 ports:
- port 1 and Port 2 are related to the first line.
- Port 3 and Port 4 are related to the second line.
Before coupling the 2 lines, i succeeded to obtain an S21= -0.1 dB ( for the first line) and an S43=-0.10 dB (for the second line) which are very good.
The problem is that when i tried to couple the lines, my maximum S31 or S41 is - 4.9 dB which is not good at all :-( , since i am trying to couple all the power from the forst line to the second (-1dB<S31 & S41<0 dB)
What are the boundaries to use?
Can you help me please to have an S31 or an S41 less than -1.5 dB :roll:?
https://obrazki.elektroda.pl/18_1332170289.png
https://obrazki.elektroda.pl/90_1332170338.png
https://obrazki.elektroda.pl/5_1332170357.png
https://obrazki.elektroda.pl/38_1332170374.png