IdealMode Converter
This type of block represents a mixed mode to single ended mode converter.
The converter converts a pair of differential and common modes to a pair of single ended modes or vice versa. The conversion is defined by the equations
VD
= VP - VN,
VC = ½ (VP + VN),
ID = ½ (IP - IN), and
IC = IP + IN.
The converter may be used in a pure circuit environment (using circuit elements like R, L, C, transistors etc), or it may be connected to S-Parameter based blocks like microstrip line or CST MICROWAVE STUDIO® blocks. The converter is a lossless component that does not dissipate any power. The differential and common mode are related to the odd and even mode, respectively. See the CST MICROWAVE STUDIO® Multipin Port Overview for details about the different kinds of modes.
Note
Since the converter does not make any assumptions about reference impedances of connected blocks and external ports, it may be necessary to explicitly set the impedance of connected external ports. The most commonly used relationships between reference impedances of single ended and mixed mode S-Parameters are
ZD
= 2 ZSE and
ZC = ½ ZSE.
If the converter is used for example to convert single ended to mixed mode results in the usual 50 Ω system, the impedance of the external port connected to the differential pin should be set to 100 Ω, and the impedance of the external port connected to the common pin should be set to 25 Ω.
See also