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Concepts and Features
R&S
®
ZNB/ZNBT
155
User Manual 1173.9163.02 ─ 38
Table 4-6: Ideal standard parameters
Standard (Gender)
R (Load)
Electrical Length (Offset)
Open (f, m)
∞
Ω
0 mm (Delay: 0 s)
Short (f, m)
0 Ω
0 mm
Offset Short (f, m)
0 Ω
10 mm
Match (f, m)
Z
0
(characteristic impedance of
the connector type)
0 mm
Sliding Match (f, m)
–
0 mm
Reflect (f, m)
∞
Ω
0 mm
Through (ff, mm, mf)
–
0 mm
Line (ff, mm, mf)
–
10 mm
Attenuation (ff, mm , mf)
–
0 mm
Symm. Network (ff, mm, mf)
–
0 mm
The following additional parameters are used:
●
Characteristic impedance: Z
0
(characteristic impedance of the connector type)
●
Loss: 0 dB / sqrt(GHz) or (0 GΩ / s) in Agilent mode
●
All inductance and capacitance parameters are set to zero.
4.5.2.3
Sliding Match Standards
The Sliding Match is a one-port standard consisting of an air line with a movable, low-
reflection load element (sliding load). This standard is used because a no perfect
Match is available over a wide frequency range. However, a series of measurements at
a given frequency with equal mismatch and varying phase yields reflection factors that
are located on a circle in the Smith chart. The center of this circle corresponds to per-
fect match. The network analyzer determines and further corrects this match point fol-
lowing I. Kása's circle-fitting algorithm.
To obtain the reflection coefficient for a perfectly matched calibration standard, the
Sliding Match must be measured at least at 3 positions which should be unequally
spaced to avoid overlapping data points. Increasing the number of positions to 4 – 6
can improve the accuracy. Moreover it is recommended to use the predefined load
positions of the standard.
Calibration