R&S QAR50, Руководство пользователя

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Measurements and result displays
R&S
®
QAR50
37 User Manual 1179.4992.02 ─ 02
Make sure that the plate is parallel to the clusters. We recommend using the same
fixture for the metal plate as for the DUT.
2. Select "Normalize Reflection" to initiate the normalization.
When the normalization measurement is done, the R&S QAR50 saves the correc-
tion data. The R&S QAR50 corrects all subsequent measurements accordingly.
A valid normalization results in an image with high reflection. The mean reflection
should be approximately 0
dB and should not exceed a certain deviation from that
value - refer to the datasheet for exact values.
3. Optional: Select "Measure" to verify the normalization (use the same plate as for
normalization).
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 verification, see
Chapter 11, "System verification" , on page 51.
4. Remove the plate used for normalization and continue with measuring actual
DUTs.
Normalizing the transmission and phase measurement
For the transmission and phase measurement, normalization is a free-space measure-
ment and requires no additional devices. However, make sure that the area between
the clusters is free of obstacles. A free-space measurements represents a DUT with
0
% attenuation.
1. Select "Normalize Transmission" to initiate the normalization.
When the normalization measurement is done, the R&S QAR50 saves the correc-
tion data. The R&S QAR50 corrects all subsequent measurements accordingly.
For the transmission measurement, a valid normalization results in a transmission
of approximately 0
dB attenuation. The transmission attenuation should not exceed
a certain deviation from that value - refer to the datasheet for exact values.
For the phase measurement, a valid normalization results in an image that shows
the same phase throughout the evaluation area of the image - refer to the data-
sheet for exact values.
2. Optional: Select "Measure" to verify the normalization.
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 verification, see
Chapter 11, "System verification" , on page 51.
3. Continue with measuring actual DUTs.
8.2 Measurement
The R&S QAR50 provides several measurements. Each measurement analyzes cer-
tain characteristics of the DUT.
Measurement