R&S
®
ZVL
System Overview
Basic Concepts
Quick Start Guide 1303.6538.62-01
82
An extended range of formats and conversion formulas is available for markers. To
convert any point on a trace, create a marker and select the appropriate marker format.
Marker and trace formats can be selected independently.
3.1.7.3 Polar
Diagrams
Polar diagrams show the measured data (response values) in the complex plane with a
horizontal real axis and a vertical imaginary axis. The grid lines correspond to points of
equal magnitude and phase.
E
The magnitude of the response values corresponds to their distance from the
center. Values with the same magnitude are located on circles.
E
The phase of the response values is given by the angle from the positive horizontal
axis
.
Values with the same phase on straight lines originating at the center.
The following example shows a polar diagram with a marker used to display a pair of
stimulus and response values.
Example: Reflection coefficients in polar diagrams
If the measured quantity is a complex reflection coefficient (S
11
, S
22
etc.), then the
center of the polar diagram corresponds to a perfect load Z
0
at the input test port of the
DUT (no reflection, matched input), whereas the outer circumference (|S
ii
| = 1)
represents a totally reflected signal.
Examples for definite magnitudes and phase angles:
E
The magnitude of the reflection coefficient of an open circuit (Z = infinity, I = 0) is
one, its phase is zero.
