GUI Reference
R&S
®
ZNC
136
User Manual 1173.9557.02 ─ 13
Background information
Refer to the following sections:
●
chapter 3.2.4, "Display Formats and Diagram Types"
●
chapter 3.2.4.6, "Measured Quantities and Display Formats"
Access:
TRACE > FORMAT key or Alt + Shift + B
dB Mag
Selects a Cartesian diagram with a logarithmic scale of the vertical axis to display the
magnitude of the complex measured quantity.
Properties:
The stimulus variable appears on the horizontal axis, scaled linearly. The
magnitude of the complex quantity C, i.e. |C| = sqrt ( Re(C)
2
+ Im(C)
2
), appears on the
vertical axis, scaled in dB. The decibel conversion is calculated according to dB Mag(C)
= 20 * log(|C|) dB.
Application:
dB Mag is the default format for the complex, dimensionless S-parameters.
The dB-scale is the natural scale for measurements related to power ratios (insertion
loss, gain etc.).
Tip (alternative formats):
The magnitude of each complex quantity can be displayed on
a linear scale. It is possible to view the real and imaginary parts instead of the magnitude
and phase. Both the magnitude and phase are displayed in the polar diagram.
Remote command:
MLOGarithmic
Phase
Selects a Cartesian diagram with a linear vertical axis to display the phase of a complex
measured quantity in the range between –180 degrees and +180 degrees.
Properties:
The stimulus variable appears on the horizontal axis, scaled linearly. The
phase of the complex quantity C, i.e. φ (C) = arctan ( Im(C) / Re(C) ), appears on the
vertical axis. φ (C) is measured relative to the phase at the start of the sweep (reference
phase = 0°). If φ (C) e180° the curve jumps by –360°; if it falls below –180°, the
trace jumps by +360°. The result is a trace with a typical sawtooth shape. The alternative
"Phase Unwrapped" format avoids this behavior.
Trace Settings