National Instruments NI PXIe-5624, Calibration Procedure

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NI PXIe-5624R Calibration Procedure
5. Configure the NI 5624R with the following settings:
• DDC mode
• Center frequency: The first frequency listed in the NI 5624R Center Frequency (MHz)
column in Table 3.
• I/Q rate: 500 MHz
• Dither: On (High)
6. Configure the signal generator with the following settings:
• Frequency: The first frequency listed in the Generator Start Frequency (MHz) column
in Table 3
• Power level: 4 dBm
7. Configure the power sensor to correct for the current frequency of the signal generator
using the power sensor frequency correction function.
8. Use the power sensor to measure the power. Record the result as measured input power .
Note Power sensor readings are in dBm, not watts.
9. Calculate the corrected input power using the following equation:
corrected input power = measured input power + splitter balance
Tip Find the splitter balance by using the appropriate data points from the
Characterizing Power Splitter Balance section.
10. Perform an acquisition and measure the tone present at the frequency generated by the
signal generator.
11. Calculate the absolute amplitude accuracy using the following equation:
absolute amplitude accuracy = NI 5624R input power – corrected input power
Table 3. Configured Center Frequencies
NI 5624R Center
Frequency (MHz)
Generator Start
Frequency (MHz)
Generator Stop
Frequency (MHz) Step Size (MHz)
225 25 425 5
500 300 700 5
800 600 995 5
1200 1005 1400 5
1500 1300 1700 5
1800 1600 1975 5