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 Zo, and are related to the cal coefficients - Offset Zo, Offset Loss, and Offset Delay - as follows:
Recall that
Equation 2
L ≈ L0 + ωR
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