National Instruments PXIe-5164, Руководство пользователя

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• Averaging: automatic
• Averaging resolution: 4 (0.001 dB)
• Aperture: 20 ms
4. Call the niHsai Group B External Cal API v1 Host.lvclass:Passband Flatness Cal
Configure VI to obtain the amplitude and frequency of the sine waveform to generate.
Configure the signal generator to output a sine waveform with the specified amplitude
plus
splitter loss and frequency into a 50 Ω load.
Note Select the splitter loss value from the list of test points from the Test
System Characterization section for the current Test Point Frequency.
5. Enable the signal generator output if not already enabled.
6. Configure the power sensor to correct for the current sine wave frequency using the
power sensor frequency correction function.
7. Wait 0.1 second for settling.
8. Use the power sensor to measure the power in dBm. Record the result as
measured
input power
.
9. Calculate the corrected input power using the following equation:
corrected input power
=
measured input power
+
splitter balance
Note Select the
splitter balance
value from the list of test points from
the Test System Characterization section for the current Test Point Frequency.
10. Call the niHsai Group B External Cal API v1 Host.lvclass:Passband Flatness Cal Adjust
VI with the following settings:
•
actual frequency generated (Hz) : The frequency of the sine waveform present on
the specified channel of the PXIe-5164
• actual amplitude generated (dBm) : The corrected input power of the sine
waveform present on the specified channel of the PXIe-5164
11. Repeat steps 4 through 10 until the passband flatness cal complete indicator from the
niHsai Group B External Cal API v1 Host.lvclass:Passband Flatness Cal Adjust VI
returns TRUE.
12. Disable the signal generator output.
Return to the main Adjusting the PXIe-5164 task.
Adjusting 1 M
Ω
Passband Amplitude Flatness and
Bandwidth
Follow this procedure to adjust the 1 MΩ passband amplitude flatness and bandwidth of the
PXIe-5164
1.
Place the 50 Ω feed-thru terminator between the splitter output and the SMA (m)-to-BNC
(m) adapter of splitter output 2. Connect splitter output 2 of the power sensor assembly
from the
Test System Characterization section to the specified channel of the PXIe-5164.
Note The power sensor assembly must match the configuration used in the
Test System Characterization section, in which the power sensor is connected to
48 | ni.com | PXIe-5164 Calibration Procedure