R&S QAR50, Руководство пользователя

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Measurements and result displays
R&S
®
QAR50
36 User Manual 1179.4992.02 ─ 02
8 Measurements and result displays
The R&S QAR50 provides several measurements and result displays that you can use
to evaluate the quality of a DUT.
Measurements usually consist of two steps, normalization and the actual measure-
ment.
1. Set up the normalization.
2. Perform the normalization.
For details about measurement normalization, see Chapter 8.1, "Normalization" ,
on page 36.
3. Place the DUT between the clusters.
4. Start the measurement.
For details about measurement, see Chapter 8.2, "Measurement" , on page 37.
5. Evaluate the measurement results using the result displays.
For details about the result displays, see Chapter 8.3, "Result displays" ,
on page 41.
8.1 Normalization
Normalization is a separate measurement that provide a baseline to which other mea-
surements are compared.
Reflection and transmission measurements must be normalized separately by two sep-
arate measurements.
It is not necessary to normalize every measurement. We recommend normalizing the
measurement regularly. Refer to the datasheet for more information about recommen-
ded normalization intervals.
In addition, the software shows a message if normalization becomes necessary
because of temperature changes or other circumstances.
Normalizing reflection measurements
Normalizing the reflection measurement requires a clean, smooth and flat metallic
plate for a high reflection, for example aluminum. Such a metal plate represents a DUT
with 100
% reflectivity. Make sure to use a plate that has a size of at least 300 mm x
300 mm.
If you own the verification kit, you can use the verification plate labeled "E" to normal-
ize the measurement.
1. Place the plate between the clusters at the location where the DUT would be.
Normalization