Agilent Technologies E5071C Manual page 187

E5071C
Offset Z0
The offset impedance between the standard to be defined and the actual
measurement plane. Normally, this is set to the system's characteristic
impedance.
Offset Delay
The delay that occurs depending on the length of the transmission line
between the standard to be defined and the actual measurement plane. In
an OPEN, SHORT, or LOAD standard, the delay is defined as one-way
propagation time (sec.) from the measurement plane to the standard. In a
THRU standard, it is defined as one-way propagation time (sec.) from one
measurement plane to the other. The delay can be determined through
measurement or by dividing the exact physical length of the standard by
the velocity coefficient.
Offset Loss
This is used to determine the energy loss caused by the skin effect along
the length (one-way) of the coaxial cable. Loss is defined using the unit of
ohm/s at 1 GHz. If you select waveguide as the media type, this parameter
is ignored. In many applications, using the value 0 for the loss should not
result in significant error. The loss of a standard is determined by
measuring the delay (sec.) and the loss at 1 GHz and then substituting
them in the formula below.
C0, C1, C2, C3
It is extremely rare for an OPEN standard to have perfect reflection
characteristics at high frequencies. This is because the fringe capacitance of
the standard causes a phase shift that varies along with the frequency. For
internal calculation of the analyzer, an OPEN capacitance model is used. This
model is described as a function of frequency, which is a polynomial of the
third degree. Coefficients in the polynomial may be defined by the user. The
formula for the capacitance model is shown below:
F: measurement frequency
C0 unit: (Farads) (constant in the polynomial)
C1 unit: (Farads/Hz)
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