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PXIe-5665 Calibration Procedure
10. Set the RF source 1 frequency to
P1 Frequency
.
11. Set the RF source 2 frequency to
P2 Frequency
.
12. Set the PXIe-5665 center frequency to
IMD Low Frequency
.
13. Commit the PXIe-5665 settings to hardware.
14. Enable the RF source 1 and RF source 2 outputs.
15. Wait 2.5 s before making the first measurement and wait 100 ms before making subsequent
measurements to allow the PXIe-5665, RF source 1, and RF source 1 amplitudes to settle.
Note
Settling times are a characteristic of the RF source device. Refer to the
section of this document for a list of NI-recommended source devices and
device specifications. If you use an RF source device with different device
specifications, your settling times may differ from those listed in this procedure.
16. Measure the power spectrum with the PXIe-5665.
17. Find the highest peak within the measurement bandwidth. This value is the
IMD Low
Power
.
18. Repeat steps 11 to step 16 for the PXIe-5665 center frequencies of
P1 Frequency
,
P2 Frequency
, and
IMD High Frequency
. The values from step 16 are
IMD Low Power
,
P1 Power
,
P2 Power
, and
IMD High Power,
respectively.
19. Calculate the upper and lower TOI points using the following equations:
TOI Upper= P1 Power + (P2 Power - IMD High Power)/
2
TOI Lower= P2 Power + (P1 Power - IMD Low Power)/
2
The smaller value of the
TOI Lower
and
TOI Upper
is the
TOI Minimum
.
20. Repeat steps 8 to 18 for all test frequencies in Table 32.
21. Repeat steps 5 to 19 with the PXIe-5665 preamplifier enabled for frequencies greater than
or equal to 3.6 GHz.
Table 33.
PXIe-5665 14 GHz VSA TOI (Frequencies >700 MHz)
Verification Test Frequencies
Preamp Enabled
Start Frequency
Stop Frequency
(GHz)
Step Size (MHz)
Enabled
800 MHz
3.3
500
Disabled
800 MHz
3.3
500
3.6 GHz
13.6
500
13.99895 GHz
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