Agilent Technologies 8510 - Manual (Page 29)

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Appendix C
Cal coefficients model
Offset devices like offset shorts and offset opens can
be modeled by the following signal flow graph :
Figure 1 Signal flow graph model of offset devices
The offset portion of the open or short, is modeled
as a perfectly uniform lossy air dielectric transmis-
sion line. The expected coefficient of reflection,
Γ,
of the open or short then can be solved by signal
flow graph technique.
Equation 1
The terms Z
o
, and are related to the cal
coefficients - Offset Z
o
, Offset Loss, and Offset
Delay - as follows:
Recall that
Equation 2
L ≈ L +
0
R
ω