National Instruments PXIe-5673, Процедура калибровки

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PXIe-5673 Calibration Procedure | © National Instruments | 19
• Resolution bandwidth: 500 Hz
• Sweep time: 5 ms
• Reference clock source: External
9. Use the spectrum analyzer to measure the mean amplitude of the first close-in IMD tone at
86.7 MHz (LO + 2
F
1
-
F
2
). Name this value
I
1
. Use the following spectrum analyzer
parameter settings:
•
Center frequency: (Frequency in step 5) +
F
1
• Reference level: 0 dBm
• Frequency span: 0 Hz
• Resolution bandwidth: 500 Hz
• Sweep time: 5 ms
• Reference clock source: External
10. Use the spectrum analyzer to measure the mean amplitude of the second close-in IMD tone
at 87.6 MHz (LO + 2
F
2
-
F
1
). Name this value
I
2
. Use the following spectrum analyzer
parameter settings:
•
Center frequency: (Frequency in step 5) +
F
2
• Reference level: 0 dBm
• Frequency span: 0 Hz
• Resolution bandwidth: 500 Hz
• Sweep time: 5 ms
• Reference clock source: External
11. Calculate output IMD using the following equation:
Output IMD
=
Large IMD tone power (I
1
or I
2
)
-
Small fundamental tone power (P
1
or P
2
)
12. Compare the
Output IMD
value from step 11 to the corresponding limit in Table 8.
13. Repeat steps 5 through 12 for the following frequency ranges in 250 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.