System Overview
R&S
®
ZVT
66
Getting Started 1300.0045.62 ─ 10
●
The center of the
Γ
plane (
Γ
= 0) is mapped to the reference admittance Y
0
,
whereas the circle with |
Γ
| = 1 is mapped to the imaginary axis of the Y plane.
●
The circles for the points of equal conductance are centered on the real axis and
intersect at Y = infinity. The arcs for the points of equal susceptance also belong to
circles intersecting at Y = infinity (short circuit point (–1, 0)), centered on a straight
vertical line.
Examples for special points in the inverted Smith chart:
●
The magnitude of the reflection coefficient of a short circuit (Y = infinity, U = 0) is
one, its phase is –180 deg.
●
The magnitude of the reflection coefficient of an open circuit (Y = 0, I = 0) is one, its
phase is zero.
3.2.4.6
Measured Quantities and Display Formats
The analyzer allows any combination of a display format and a measured quantity. The
following rules can help to avoid inappropriate formats and find the format that is ide-
ally suited to the measurement task.
●
All formats are suitable for the analysis of reflection coefficients S
ii
. The formats
"SWR", "Smith" and "Inverted Smith" lose their original meaning (standing wave
ratio, normalized impedance or admittance) if they are used for transmission S-
parameters, ratios and other quantities.
●
The complex "Impedances", "Admittances", "Z-parameters", and "Y-parameters"
are generally displayed in one of the Cartesian diagrams with linear vertical axis
scale or in a polar diagram.
●
The real "Stability Factors", "DC Inputs", and the "PAE" is generally displayed in a
linear Cartesian diagram ("Lin Mag" or "Real"). In complex formats, real numbers
represent complex numbers with zero imaginary part.
The following table gives an overview of recommended display formats.
Screen Elements
