elektr0
Full Member level 5
Hello,
studying symmetric coupled microstrip lines, we identifiy to modes of propagation (common mode and differential mode).
Whereas the even and odd mode impedances, commonly used for microwave design purposes, are defined for half of the structure.
Zeven = V/I, if a perfect magnetic wall is placed between the strips.
Zodd = V/I, if a perfect electric wall is placed between the strips.
Lets say Zcommon = 20 Ohm, Zdifferential = 60 Ohm.
It appears Zeven=2*Zcommon=40 Ohm, Zodd=0.5*Zdifferential = 30 Ohm.
In this sense, Zcommon is the series connection of Zeven (first line) and Zeven (second line),
while Zdifferential is the parallel connection of Zodd (first line) and Zodd (second line).
Zcommon = Zeven1+Zeven2
Zdifferential = (Zodd1*Zodd2)/(Zodd1+Zodd2)
If we know think of an asymmetric configuration.
Left strip width differs from right strip width.
Is it still possible to use the above equations.
Series connection of two different Zeven values and parallel connection of two different Zodd values. ???
Thanks for your comments.
-e
studying symmetric coupled microstrip lines, we identifiy to modes of propagation (common mode and differential mode).
Whereas the even and odd mode impedances, commonly used for microwave design purposes, are defined for half of the structure.
Zeven = V/I, if a perfect magnetic wall is placed between the strips.
Zodd = V/I, if a perfect electric wall is placed between the strips.
Lets say Zcommon = 20 Ohm, Zdifferential = 60 Ohm.
It appears Zeven=2*Zcommon=40 Ohm, Zodd=0.5*Zdifferential = 30 Ohm.
In this sense, Zcommon is the series connection of Zeven (first line) and Zeven (second line),
while Zdifferential is the parallel connection of Zodd (first line) and Zodd (second line).
Zcommon = Zeven1+Zeven2
Zdifferential = (Zodd1*Zodd2)/(Zodd1+Zodd2)
If we know think of an asymmetric configuration.
Left strip width differs from right strip width.
Is it still possible to use the above equations.
Series connection of two different Zeven values and parallel connection of two different Zodd values. ???
Thanks for your comments.
-e