Characteristic Impedance
Characteristic impedance is a transmission line parameter that determines how propagating signals are transmitted or reflected in the line. The following equation and figures represent the components of characteristic impedance.
Z0= |  |
where
Z0 is the characteristic impedance
L is the inductance per length
C is the capacitance per length
R is the resistance per length
G is the dielectric conductance per length
is the frequency (radians/s)
If a transmission line is in the system, its characteristic impedance must also match the source and the load for maximum power transfer.
In an ideal, lossless transmission line, there is no series resistance or dielectric loss, as shown by the following formula:
| R = 0 G = 0 | => | Z0 = |  | (frequency independent) |
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Maximum power is transferred in a system from the source to the load when both have the same impedance, as shown in the following figure:
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