Keysight Technologies N9340B, User Manual

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Making Measurements
Making a Reflection Calibration Measurement
59
Making a Reflection Calibration
Measurement
The following procedure makes a reflection
measurement using a coupler or directional bridge to
measure the return loss of a filter. This example uses a
370 MHz low-pass filter as the DUT.
The calibration standard for reflection measurements is
usually a short circuit connected at the reference plane
(the point at which the DUT is connected). A short circuit
has a reflection coefficient of 1 (0 dB return loss). It
reflects all incident power and provides a convenient 0
dB reference.
1 Connect the DUT to the directional bridge or coupler
as shown below. Terminate the unconnected port of
the DUT.
Figure 4-19
Reflection Measurement Short Calibration Test
Setup
N9340A
HANDHELD SPECTRUM ANALYZER
100 kH z - 3.0 GHz
PRESET
EN TER
FREQ SPAN AM PTD
BW/
SWP
SYS M ODE M EAS TRACE
ESC/ CLR
2
DEF
3
GHI
1
ABC
5
M NO
4
JKL 6PQR
8
V WX
7
STU
9
Y Z_
0
SAV E LIM IT
M ARKER
Coupled Port
Short
Circuit
DUT
or
NOTE
If possible, use a coupler or bridge with the correct test port
connector types for both calibrating and measuring. Adapters
between the test port and DUT degrades coupler/bridge
directivity and system source match.
For best response, use the same adapter for the calibration
and the measurement. Terminate the second port of a two
port device.