VNA0440
–
VNA0440e
VNA0460
–
VNA0460e
user manual V3.1
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Impedance Smith
The Smith chart is often used to show complex impedances in a complex plane and is very
well suited to calculate graphically how to match circuits. It also gives you a quick
overview of matching (The closer to the center, the better the match into 50 ohm). The
Smith chart can also show complex admittances and matching (SWR circles).
Impedance calibration graphs
The software also allows displaying the calibration measurements Open, Short and Load.
These are displayed as the measured S-parameter of the calibration termination, through
the used measurement setup.
Cal Source Impedance
When the Open, Short and Load calibrations have been done, the software can calculate
the actual source impedance that the test setup presents at the reference plane. The DUT
is excited with this source impedance. It is represented in a Smith Chart.
Gain Graphs
There is less abundance of graphs to represent the measured gain.
Gain
The Gain chart gives you gain (or attenuation) in a two port measurement. It show
magnitude and phase with two separate lines. The phase can also be represented as a
Group Delay
which is an indication of phase distortion of a DUT.
Gain Linear
The Linear Gain chart is the same gain and phase but with the gain on a linear scale.
Gain polar
The polar gain graph gives you the same information as the gain graph (magnitude and
phase), but in a single line and in the complex polar plane.
Gain calibration graphs
The Isolation and Through calibrations can be displayed in the respective graphs.
Cal Sink Impedance
During the Through calibration, the VNA measures not only the signal that arrives at a
port from the other port but the VNA also has the opportunity to measure the impedance
that the receiving port presents (through the test setup) to the signal source. This Sink
Impedance can be presented in a Smith Chart.
