R&S ZNL, User Manual

Page: 385 / 1135

VNA GUI reference
R&S
®
ZNL/ZNLE
385 User Manual 1178.5966.02 ─ 19
A "Stimulus" shift can be used in cartesian and in complex diagrams. The visible effect
depends on the diagram type:
●
In cartesian diagrams, the trace is shifted relative to the markers and the x-axis.
●
In complex diagrams, the trace is not affected.
Remote command:
DISPlay[:WINDow<Wnd>]:TRACe<WndTr>:X:OFFSet
Mag / Phase / Real / Imag ← Shift Trace
Modifies the active trace by adding and/or multiplying complex constants.
The trace points are modified according to the following formula:
        
     
Imag Real 10
180 / Phase dB 20 / Magnitude
j e a M M
j
old new
The formula and the different constants are adjusted to the different display formats of
a trace:
●
The "Mag" factor shifts a dB Mag trace in vertical direction, leaving the phase of a
complex parameter unchanged.
●
The "Phase" factor rotates a trace that is displayed in a polar diagram around the
origin, leaving the magnitude unchanged.
●
The "Real" value shifts a real trace in vertical direction, leaving the imaginary part
unchanged.
●
The "Imag" value shifts an imaginary trace in vertical direction, leaving the real part
unchanged.
Tip: Shifting the trace by constant values is a simple case of trace mathematics. Use
the "User Def Math" dialog to define more complicated mathematical operations (see
Chapter 10.6.4.2, "User Def Math dialog" , on page 357).
Remote command:
DISPlay[:WINDow<Wnd>]:TRACe<WndTr>:Y:OFFSet
Shift Reset
Resets the static shifting, defined using Stimulus and Mag / Phase / Real / Imag ,
respectively.
Tracking Mode/Ref Sweep Point
Allows you to take the trace value at a selected sweep point as the reference point for
a dynamic shift of the active trace.
With a raw complex trace value z = Re(z) + j·Im(z) = |z| e
j·φ(z)
and a raw complex value
zr = Re(zr) + j·Im(zr) = |zr| e
j·φ(zr)
at the reference point (for the current sweep), the
dynamically shifted trace value Dyn_Shift(z) is calculated as follows:
"Amplitude" Dyn_Shift(z) = z / |zr|
"Phase"
Dyn_Shift(z) = z e
-j·φ(zr)
"Real" Dyn_Shift(z) = z – Re(zr)
"Imag" Dyn_Shift(z) = z – Im(zr)
"Complex" Dyn_Shift(z) = z – zr
Remote command:
n.a.
Trace softtool