R&S QAR Series, Руководство пользователя

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Operating the R&S QAR
R&S
®
QAR
35 User Manual 1178.7200.02 ─ 04
The measurement itself lasts less than a second. The results are displayed after a
few seconds.
For details on how to run the measurement, see
Chapter 5.1.3.2, "Reflection Mea-
surement" , on page 36 and Chapter 5.1.3.3, "Transmission Measurement" ,
on page 37.
● Normalization .......................................................................................................... 35
● Reflection Measurement ......................................................................................... 36
● Transmission Measurement ....................................................................................37
5.1.3.1 Normalization
Normalization is a separate measurement that determines systematic, reproducible
measurement deviations. Determining these measurement deviations allows you to
remove those deviations from the actual measurement results, which in turn improves
the accuracy of the measurement.
Normalizing reflection measurements
Normalizing the reflection measurement requires a clean, smooth and flat metallic
plate for a high reflectivity, for example aluminum. The recommended size is between
100
mm x 100 mm and 200 mm x 200 mm.
If you have the verification objects, and it fits your setup, you can use the plate labeled
E to normalize the reflection.
1. Place the plate at the same location where you are going to mount the DUT for the
actual measurement.
Make sure that the plate is parallel to the R&S
QAR. We recommend using the
same fixture for the metal plate as for the DUT.
2. Select the "Normalize Reflection" button to initiate the measurement.
When the normalization measurement is done, the R&S QAR saves the correction
data. All subsequent measurements are corrected accordingly.
A valid normalization results in an image with high reflectivity. The mean reflectivity
should be approximately 0
dB and should not exceed a certain deviation from that
value - refer to the datasheet for exact values.
3. Optional: Scan the metal plate with the "Measure" button to verify the normaliza-
tion.
If the results do not meet the expectations, repeat the normalization.
If the second normalization still yields unexpected results, verify the test setup. For
details about the verification procedure, see
Chapter 5.1.5, "Verification" ,
on page 40.
Radome Measurements