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ni.com
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PXIe-5673 Calibration Procedure
10. Repeat steps 8 through 9 for the following frequency ranges in 20 MHz increments,
including endpoints:
•
PXI-5650: 85 MHz to 1.3 GHz
•
PXI-5651: 85 MHz to 3.3 GHz
•
PXI-5652: 85 MHz to 6.6 GHz
Store the resulting measurements.
11. Set the niRFSG Power Level property to
0
dBm, and repeat steps 8 through 10.
12. Set the niRFSG Power Level property to
-30
dBm, and repeat steps 8 through 10,
measuring the power using both the power meter and spectrum analyzer. Use the following
parameter settings for the spectrum analyzer:
•
Center frequency: (Frequency in step 8) + 1 MHz
•
Reference level: -30 dBm
•
Frequency span: 0 Hz
•
Resolution bandwidth: 500 Hz
•
Sweep time: 20 ms
•
Reference clock source: External
•
Attenuation: 5 dB
•
Preamplifier: niRFSG Power Level property
13. Use the power meter measurements to calculate a correction for the spectrum analyzer
inaccuracies and attenuator loss with the following equation:
Corrections [i]
=
Power Meter [i]
-
SpecAn [i]
Note
The
SpecAn [i]
values in the above equation are used only to determine the
Corrections [i]
values that are used in the
-60
dBm and
-90
dBm measurements
described in steps 14 and 15. When verifying the
-30
dBm measurements, you need
to use only the
Power Meter [i]
values.
14. Set the niRFSG Power Level property to
-60
dBm, and repeat steps 8 through 10 using
only the spectrum analyzer and its measured correction to measure the power accuracy
using the following spectrum analyzer parameter settings:
•
Center frequency: (Frequency in step 8) + 1 MHz
•
Reference level: -30 dBm
•
Frequency span: 0 Hz
•
Resolution bandwidth: 500 Hz
•
Sweep time: 20 ms
•
Reference clock source: External
•
Attenuation: 5 dB
•
Preamplifier: On
