VNA0440
–
VNA0440e
VNA0460
–
VNA0460e
user manual V3.1
- 50 -
Matching procedure
1.
In the Smith chart, put a
marker
on the center of the frequency band that needs to
be matched. This is Marker 1 in the previous graph.
2.
Right-click on the marker or on the readout and from the menu select
Match Circuit
.
3.
The VNA software opens the
Match Calculator
. Depending on the original
impedance, this will give you two or four possible match circuits and the resulting
impedances. The resulting -10dB bandwidth is indicated at the bottom of each
possibility.
4.
The user can select the circuit of his or her preference.
A low pass structure with series inductors is often a
good choice because it provides some added low pass
filtering to reduce harmonic emissions.
5.
The
sliders
around the matching components can be used to fine-tune the values, to
optimize the
bandwidth
of the resulting match and to set them to E-series values.
The right picture shows that it is advantageous to make the Smith graph swing around
the center (50Ohm) to increase the -10dB bandwidth to 340MHz.
6.
Use the
Select
button to select the desired matching circuit. The software will apply
this circuit on the Smith chart and show the result of the match. Use the
Copy Match
