National Instruments NI PXIe-5601, Calibration Procedure

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NI PXIe-5601 Calibration Procedure | © National Instruments | 33
34. Repeat steps 14 to 32 for the last eight rows of Table 20, setting the niRFSA Mechanical
Attenuator Enabled property or the
NIRFSA_ATTR_MECHANICAL_ATTENUATOR_ENABLED
attribute as indicated in the
table.
35. Read the device temperature using the niRFSA Device Temperature property or the
NIRFSA_ATTR_DEVICE_TEMPERATURE
attribute. Average this reading with the
temperature reading from step 13. Record this average for use in the Reference Level
Adjustment for RF Frequencies ≤ 120 MHz section.
36. Close the NI 5601 Reference Level Calibration step using the niRFSA Close Calibration
Step VI or the
niRFSA_CloseCalibrationStep
function.
37. Close the external calibration by calling the niRFSA Close Ext Cal VI with the action
parameter set to Commit or by calling the
niRFSA_CloseExtCal
function with the
action parameter set to
NIRFSA_VAL_EXT_CAL_COMMIT
.
38. Close the niRFSG session using the niRFSG Close VI or the
niRFSG_close
function.
IF Attenuation Calibration Adjustment
During operation, the NI 5601 uses a lookup table to determine the appropriate RF attenuation
and gain and IF attenuation settings to use at a given reference level and RF frequency. When
the RF and IF gain and attenuations are found, the NI 5601 determines the appropriate amplitude
correction for those settings.
This procedure determines amplitude corrections for the IF attenuation. Those corrections are
stored in the NI 5601.
1.
Connect the RF source to the power splitter input through the 3.5 mm-to-3.5 mm cable.
2. Connect the power splitter reference output to power sensor A.
3. Connect the other power splitter output to the NI 5601 RF IN connector through the
3.5 mm-to-3.5 mm adapter.
4. Ensure that the 50 Ω terminator is connected to the NI 5601 LO OUT connector.
5. Connect the NI 5601 IF OUT connector to power sensor B. Figure 9 shows the completed
equipment setup.
6. Create a new calibration session for the NI 5601 using the niRFSA Init Ext Cal VI or the
niRFSA_InitExtCal
function. Set the
driverSetup
string of the option string
parameter to
calAction: create
.
Note
Each step opens a new calibration session. Enter the appropriate password for
this VI. The default password for password-protected operations is
NI
.
7. Initialize the IF Attenuation Calibration step using the niRFSA Initialize Calibration Step
VI or the
niRFSA_InitializeCalibrationStep
function. Set the calibration step
parameter in the VI to IF Attenuation Calibration , or set the calibrationStep parameter
in the function to
NIRFSA_VAL_EXT_CAL_IF_ATTENUATION_CALIBRATION
.
8. Initialize the NI PXI/PXIe-5652 using the niRFSG Initialize VI or the
niRFSG_init
function.