National Instruments PXIe-5611 Manual

CALIBRATION PROCEDURE
NI PXIe-5611
This document describes processes to calibrate the NI PXIe-5611 I/Q
modulator. This document provides performance tests to verify if the
instrument is performing within the published specifications. For more
information about calibration, visit ni.com/calibration.
Contents
Conventions ............................................................................................ 2
Software Requirements ........................................................................... 2
Documentation Requirements................................................................. 3
Password ................................................................................................. 4
Calibration Interval ................................................................................. 4
Calibration Overview.............................................................................. 4
Test Equipment ....................................................................................... 6
Test Conditions ....................................................................................... 7
Calibration Procedures ............................................................................ 7
Initial Setup...................................................................................... 8
Verification ...................................................................................... 11
Verifying LO Filter Response .................................................. 11
Verifying LO Path Gain ........................................................... 12
Verifying Modulation Impairments.......................................... 13
Verifying Modulation Bandwidth and Impairments ................ 15
Verifying RF Path Gain............................................................ 17
Adjustment....................................................................................... 21
Adjusting LO Filter Response .................................................. 21
Adjusting LO Path Gain ........................................................... 22
Adjusting Modulation Impairments.......................................... 23
Adjusting RF Path Gain............................................................ 24
Appendix A: Calibration Utilities ........................................................... 27
Calibration VI References ............................................................... 27
Where to Go for Support......................................................................... 28

NI PXIe-5611 Calibration Procedure 2 ni.com
Conventions
The following conventions are used in this document:
»The »symbol leads you through nested menu items and dialog box options
to a final action. The sequence File»Page Setup»Options directs you to
pull down the File menu, select the Page Setup item, and select Options
from the last dialog box.
This icon denotes a tip, which alerts you to advisory information.
This icon denotes a note, which alerts you to important information.
This icon denotes a caution, which advises you of precautions to take to
avoid injury, data loss, or a system crash.
bold Bold text denotes items that you must select or click in the software, such
as menu items and dialog box options. Bold text also denotes parameter
names.
italic Italic text denotes variables, emphasis, a cross-reference, or an introduction
to a key concept. Italic text also denotes text that is a placeholder for a word
or value that you must supply.
monospace Text in this font denotes text or characters that you should enter from the
keyboard, sections of code, programming examples, and syntax examples.
This font is also used for the proper names of disk drives, paths, directories,
programs, subprograms, subroutines, device names, functions, operations,
variables, filenames, and extensions.
monospace bold Bold text in this font denotes the messages and responses that the computer
automatically prints to the screen. This font also emphasizes lines of code
that are different from the other examples.
monospace italic Italic text in this font denotes text that is a placeholder for a word or value
that you must supply.
Software Requirements
To calibrate the NI PXIe-5611, you must install NI-RFSG version 1.6 or
later on the calibration system. NI-RFSG includes all the VIs necessary for
calibration. You can download the latest version of NI-RFSG at
ni.com/idnet.
NI-RFSG supports programming the calibration procedures in LabVIEW.
Calibration VIs are accessible in LabVIEW from the Functions palette.
Refer to Table 1 for file locations.

©National Instruments Corporation 3 NI PXIe-5611 Calibration Procedure
For more information about calibration VIs, refer to the NI RF Signal
Generators Help, accessible at Start»All Programs»National
Instruments»NI-RFSG»Documentation»NI RF Signal Generators
Help.
Documentation Requirements
You might find the following documentation helpful as you write the
calibration procedure:
• NI PXIe-5673 Specifications
• NI PXIe-5673E Specifications
• NI PXIe-5673 Calibration Procedure
• NI PXIe-5673E Calibration Procedure
• NI 5450 Calibration Procedure
• NI PXI-5650/5651/5652 Calibration Procedure
• NI PXIe-5650/5651/5652 Calibration Procedure
• NI RF Signal Generators Getting Started Guide
•NI RF Signal Generators Help, including LabVIEW VI programming
references
These documents are installed with NI-RFSG. You can also download the
latest versions of documentation at ni.com/manuals.
This calibration procedure calibrates the NI PXIe-5611 I/Q modulator as a
stand-alone device. To calibrate the NI PXIe-5673 or NI PXIe-5673E, refer
to their calibration procedures at ni.com/manuals.
Table 1. Calibration File Locations (NI-RFSG 1.6 or Later)
File Name and Location Description
IVI\Bin\niRFSG.dll NI-RFSG driver containing the entire NI-RFSG API,
including calibration functions.
<LabVIEW > \instr.lib\niRFSG\
niRFSG5611Calibration
Folder containing NI-RFSG calibration API VIs. You can
access calibration functions from the NI-RFSG
calibration section of the LabVIEW function palette.

NI PXIe-5611 Calibration Procedure 4 ni.com
Password
The default password for password-protected operations is NI.
Calibration Interval
The measurement accuracy requirements of your application determine
how often you should calibrate your device. NI recommends that you
perform a complete calibration for the NI 5611 at least once a year. You can
shorten this calibration interval based on the accuracy demands of your
application.
Calibration Overview
Calibration involves verification, and, if necessary, adjustment, and
reverification of the NI 5611.
Verification is the process of testing to ensure that the accuracy of the
device. Perform verification post-adjustment to determine if the adjustment
was successful.
Adjustment is the process of measuring and compensating for device
performance to improve the measurement accuracy. Performing an
adjustment updates the calibration date.
Perform a complete calibration to guarantee successful adjustment and
performance of the NI 5611 for a one-year calibration interval. After
adjustment, repeat verification to ensure that the device meets the
calibration test limits.
After calibrating the NI 5611 as a stand-alone device, NI strongly
recommends that you calibrate the NI 5673, which includes the NI 5611.
To calibrate the NI PXIe-5673 or NI PXIe-5673E, refer to their calibration
procedures at ni.com/manuals.

©National Instruments Corporation 5 NI PXIe-5611 Calibration Procedure
Figure 1 shows the programming flow for a complete calibration.
Figure 1. Complete Calibration Programming Flow
Document
Post-Adjustment
Results
Document
Pre-Adjustment
Results
Calibration/
Verification
Complete
Ye s N o
Verify
Meets
Test Limits?
Review Verification/
Adjustment Procedure
or Return Device
Adjust (Calibration Dates
and Temperatures Updated)
Verify

NI PXIe-5611 Calibration Procedure 6 ni.com
Test Equipment
Table 2 lists the equipment required to calibrate the NI 5611. If you do not
have the recommended equipment, select a substitute calibration standard
using the specifications listed in Table 2.
Table 2. Required Equipment Specifications for NI 5611 Calibration
Required
Equipment
Recommended
Equipment Specifications
Spectrum analyzer Rohde & Schwarz (R&S)
FSU Spectrum Analyzer
with high-frequency
preamplifier option (B23)
Frequency range: 50 MHz to 6.6 GHz
Noise floor: <–152 dBm/Hz to 6.6 GHz
Power meter Anritsu ML2438A and a
MA2472 diode sensor
Range: –50 dBm to +10 dBm
Frequency range: 50 MHz to 6.6 GHz
Accuracy: 0.5%
Power splitter Aeroflex/Weinschel 1593 SWR: 1.25
Amplitude tracking: <0.25 dB
NI PXIe-5450
arbitrary waveform
generator
NI PXIe-5450 This device must be fully calibrated before
calibrating the NI 5611.
NI PXI-5652 RF
signal generator
NI PXI-5652 This device must be fully calibrated before
calibrating the NI 5611.
6 dB attenuator Anritsu 41KB-6 Frequency range: DC to 12 GHz
SWR: 1.1
50 Ωterminator
(included in the
NI 5673 kit)
NI 778353-01 —
Adapter
SMA(m)-to-N(f)
S.M. Electronics SM4241 VSWR: 1.15 : 1
SMA torque wrench NI 187106-01 1 N · m
NI PXIe-5673 Cable
Accessory Kit
NI 780567-01 Matched-length I/Q semi rigid SMA cable (4)
LO semi-rigid SMA cable (1)
RF flexible SMA cable (1)
SMA adapter
plug/plug
Huber+Suhner
32_N-SMA-50-1/11-_NE
VSWR: 1.05 : 1
BNC (m) to BNC
(m) cable (36 inches)
— —

©National Instruments Corporation 7 NI PXIe-5611 Calibration Procedure
Test Conditions
Follow these guidelines to optimize the connections and the environment
during calibration:
• Verify that the NI 5611, NI 5450, and NI 5652 are properly connected
as indicated in Chapter 5, NI 5673 RF Vector Signal Generator or
Chapter 6, NI 5673E RF Vector Signal Generator in the NI RF Signal
Generators Getting Started Guide.
• Verification limits are defined assuming the same NI 5611, NI 5450,
and NI 5652 is used during adjustment and verification.
• Keep cabling as short as possible. Long cables act as antennae, picking
up extra noise that can affect measurements.
• Verify that all connections, including front panel connections and
screws, are secure.
• Ensure that the PXI Express chassis fan speed is set to HI, the fan
filters are clean, and the empty slots contain filler panels. For more
information, refer to the Maintain Forced-Air Cooling Note to Users
document available at ni.com/manuals.
• Keep relative humidity between 10% and 90%, noncondensing.
• Maintain an ambient temperature of 23 °C ±5 °C.
• Allow a warm-up time of at least 30 minutes after the chassis is
powered on. The warm-up time ensures that the NI 5611 is at a stable
operating temperature.
• Perform a self-calibration on the NI PXIe-5450 signal generator.
• Each verification procedure requires a delay to be inserted in between
configuring all devices and acquiring the measurement. This delay
may need to be adjusted depending on the instruments used but should
always be at least 1,000 ms for the first iteration, 1,000 ms when the
power level changes, and 100 ms for each other iteration.
Calibration Procedures
The calibration process includes the following steps:
1. Initial Setup—Install the device and configure it in Measurement &
Automation Explorer (MAX). Refer to Chapter 5, NI 5673 RF Vector
Signal Generator or Chapter 6, NI 5673E RF Vector Signal Generator
in the NI RF Signal Generators Getting Started Guide for more
information about how to configure your device.
2. Verification—Verify the existing operation of the device. This step
confirms whether the device is operating within its specified range
prior to adjustment.

NI PXIe-5611 Calibration Procedure 8 ni.com
3. Adjustment—Perform an external adjustment of the device that adjusts
the calibration constants of the device. The adjustment procedure
automatically stores the calibration date on the EEPROM to allow
traceability.
4. Reverification—Repeat the verification procedure to ensure that the
device is operating within its specifications after adjustment.
These procedures are described in more detail in the following sections.
Initial Setup
Refer to the NI RF Signal Generators Getting Started Guide for
information about how to install the software and hardware and how to
configure the device in MAX.
Characterizing the Power Splitter
Several procedures in this document require using a splitter that has been
characterized to remove error from future measurements. Complete the
following steps to characterize a splitter using an NI 5652, power meter,
and spectrum analyzer, as shown in Figure 2.
1. Disconnect the NI 5611 LO IN front panel connector from the NI 5652
RF OUT front panel connector.
2. Connect the power meter power sensor to the NI 5652 RF OUT front
panel connector.
3. Generate a tone with the NI 5652 with the following NI-RFSG
property settings:
• Frequency (Hz): 50 MHz
• Power Level (dBm): –10 dBm
4. Use the power meter to measure the output power.
5. Repeat steps 3 through 4 for every frequency from 50 MHz to 6.6 GHz
in 5 MHz increments, including endpoints. Store the resulting
measurements.
6. Disconnect the power sensor from the NI 5652 RF OUT front panel
connector.
Caution If you use a cable, it should be as short as possible. The cable should always be
used with the splitter for subsequent verification procedures in this document that require
a splitter.
7. Connect the power splitter input port to the NI 5652 RF OUT front
panel connector without a cable, if possible.

©National Instruments Corporation 9 NI PXIe-5611 Calibration Procedure
Caution Remember the port to which the power sensor is connected. The power sensor
must be connected to the same port for subsequent procedures in this document.
8. Connect one available port of the power splitter to the power sensor
without a cable, if possible.
9. Connect one available end of the power splitter to the 6 dB attenuator.
10. Connect the other available port of the 6 dB attenuator to the spectrum
analyzer RF INPUT front panel connector as shown in Figure 2.
11. Configure the reference level of the spectrum analyzer to –30 dBm.
The spectrum analyzer is used only for termination.

NI PXIe-5611 Calibration Procedure 10 ni.com
Figure 2. Power Splitter Characterization Setup
12. Repeat steps 3 through 4 for every frequency from 50 MHz to 6.6 GHz
in 5 MHz increments, including endpoints. Store the resulting
measurements.
13. Subtract the power measurements from step 5 from the measurements
in step 12 for each corresponding frequency. Store the resulting
calculations. The result is an array representing the loss through the
splitter for the entire needed frequency range in 5 MHz increments.
1 NI 5652 RF Signal Generator
2 Splitter
3 Power Sensor
4 Attenuator
5 Power Meter
6 CH A Connector
7 Spectrum Analyzer
8 RF INPUT Connector
123
5
6
7
8
4

©National Instruments Corporation 11 NI PXIe-5611 Calibration Procedure
Note This array is later used to compensate measurements and correct for splitter loss.
If you do not find the exact frequency needed in the splitter correction array, use the loss
corresponding to the next closest frequency.
You have successfully characterized your splitter.
Verification
This section describes the steps you must follow to verify successful
adjustment of the NI 5611.
Verification tests the following NI 5611 specifications:
• LO filter response
• LO path gain
• Modulation impairments
• Modulation bandwidth and impairments
• RF path gain
• Intermodulation products
Verification of the NI 5611 is complete only after you have successfully
completed all tests in this section.
Verifying LO Filter Response
Complete the following steps to verify the LO filter response of an NI 5611
module using a spectrum analyzer.
1. Connect the NI 5611 LO OUT front panel connector to the spectrum
analyzer RF INPUT front panel connector.
2. Connect the PXI Express chassis 10 MHz REF IN rear panel connector
to the spectrum analyzer REF OUT rear panel connector.
3. Generate a signal with the following NI-RFSG property settings:
• Frequency (Hz): 85 MHz
• Power Level (dBm): 0 dBm
• Generation Mode: CW
• LO OUT Enabled: Enabled
4. Use the spectrum analyzer to measure the mean fundamental tone
power using the following spectrum analyzer parameter settings:
• Center Frequency: Frequency from step 3
• Reference level: +5 dBm
•Frequencyspan:0Hz

NI PXIe-5611 Calibration Procedure 12 ni.com
• Resolution bandwidth: 500 Hz
• Sweep time: 5 ms
5. Use the spectrum analyzer to measure the mean tone power at the
2nd harmonic frequency using the following spectrum analyzer
parameter settings:
• Center Frequency: Frequency from step 3 × 2
• Reference level: +5 dBm
•Frequencyspan:0Hz
• Resolution bandwidth: 500 Hz
• Sweep time: 5 ms
6. Calculate the power level of the harmonic in dBc by subtracting the
measured fundamental power from step 4 from the measured harmonic
power from step 5.
7. Compare the calculated power level from step 6 to the corresponding
limit in Table 1.
8. Repeat steps 3 through 7 for every frequency from 85 MHz to 2.2 GHz
in 5 MHz increments, including endpoints.
If the results are within the selected test limit, the device has passed this
portion of the verification.
Verifying LO Path Gain
Complete the following steps to verify the LO path gain of the NI 5611
module using a power meter.
1. Connect the NI 5611 LO OUT front panel connector to the power
meter.
2. Generate a signal with the following NI-RFSG property settings:
• Frequency (Hz): 85 MHz
• Power Level (dBm): 0 dBm
• Generation Mode: CW
• LO OUT Enabled: Enabled
3. Use the power meter to measure the LO OUT power.
Table 3. LO Filter Response Verification Test Parameters
Harmonic
2nd Harmonic Upper Limits (dBc)
F ≤100 MHz 100 MHz < F ≤2.2 GHz
2nd (2F) –21 –31

©National Instruments Corporation 13 NI PXIe-5611 Calibration Procedure
4. Compare the measured LO OUT output power to the limit in Table 4.
5. Repeat steps 2 through 4 for every frequency from 85 MHz to 6.6 GHz
in 10 MHz increments, including endpoints.
If the results are within the selected test limit, the device has passed this
portion of the verification.
Verifying Modulation Impairments
Complete the following steps to verify the modulation impairments of the
NI 5611 using a spectrum analyzer.
1. Connect the NI 5611 RF OUT front panel connector to the spectrum
analyzer RF INPUT front panel connector.
2. Connect the PXI Express chassis 10 MHz REF IN rear panel connector
to the spectrum analyzer 10 MHz REF OUT rear panel connector on
the spectrum analyzer.
3. Generate a single-sideband tone with a +1 MHz offset from the carrier
signal with the following NI-RFSG property settings:
• Frequency (Hz): 85 MHz
• Power Level (dBm): 0 dBm
• Generation Mode: Arb Waveform
• Reference Clock Source: ClkIn
The image appears at 84 MHz, and the carrier leakage at 85 MHz.
4. Use the spectrum analyzer to measure the mean power of the RF output
using the following spectrum analyzer parameter settings:
• Center frequency: Frequency in step 3 + 1 MHz
• Reference level: +5 dBm
•Frequencyspan:0Hz
• Resolution bandwidth: 500 Hz
• Sweep time: 5 ms
• Reference clock source: External
Note Zero-span mode shortens test time by avoiding unnecessary frequency sweeping.
To obtain the average power, convert the zero-span trace data to linear volts, perform a
mean calculation, and then convert the linear volts back to dBm.
Table 4. LO Path Gain Verification Upper Test Limits
LO OUT Power (dBm)
As Found LO OUT Power
Accuracy Test Limits (dB)
As Left LO OUT Power
Accuracy Test Limits (dB)
0±2.0 ±1.0

NI PXIe-5611 Calibration Procedure 14 ni.com
5. Use the spectrum analyzer to measure the mean power of the image
using the following spectrum analyzer parameter settings:
• Center frequency: Frequency in step 3 – 1 MHz
• Reference level: +5 dBm
•Frequencyspan:0Hz
• Resolution bandwidth: 500 Hz
• Sweep time: 5 ms
• Reference clock source: External
6. Use the spectrum analyzer to measure the mean power of the carrier
using the following spectrum analyzer parameter settings:
• Center frequency: Equivalent to the frequency in step 3
• Reference level: +5 dBm
•Frequencyspan:0Hz
• Resolution bandwidth: 500 Hz
• Sweep time: 5 ms
• Reference clock source: External
7. Calculate the image suppression ratio (ISR) and carrier suppression
ratio (CSR) according to the following formulas and save the values:
ISR = Measured Image Power – Measured RF Output Power
CSR = Measured Carrier Leakage Power – Measured RF Output
Power
8. Repeat steps 3 though 7 for each LO frequency from 85 MHz to
6.6 GHz in 10 MHz steps, including endpoints.
Note With the baseband set to 1 MHz, 0 dBm single-sideband tone, the RF output is
always 1 MHz above the LO frequency, the image is 1 MHz below LO, and the carrier
leakage is at LO frequency.
9. Use Table 5 to compare the ISR and CSR from step 7 for each LO
frequency.
Table 5. Modulation Impairments Verification Upper Test Limits
LO Frequency
(MHz)
ISR (dBc)
Test Limit
CSR (dBc)
Test Limit
85 to 400 –43 –44
400 to 2,500 –50 –44

©National Instruments Corporation 15 NI PXIe-5611 Calibration Procedure
If the results are within the selected test limit, the device has passed this
portion of the verification.
Verifying Modulation Bandwidth and Impairments
Complete the following steps to verify the modulation bandwidth
performance and modulation impairments of the NI 5611 using a spectrum
analyzer.
1. Connect the NI 5611 RF OUT front panel connector to the spectrum
analyzer RF INPUT front panel connector.
2. Connect the PXI Express chassis 10 MHz REF IN rear panel connector
to the spectrum analyzer 10 MHz REF OUT rear panel connector on
the spectrum analyzer.
3. Generate an I/Q tone at –50 MHz offset from the carrier with the
following NI-RFSG property settings:
• Frequency (Hz): 200 MHz
• Power Level (dBm): 0 dBm
• Generation Mode: Arb Waveform
• Reference Clock Source: ClkIn
4. Use the spectrum analyzer to measure the mean output power of the RF
output using the following spectrum analyzer parameter settings:
• Center frequency: frequency in step 3 + offset in step 3
• Reference level: +5 dBm
•Frequencyspan:0Hz
• Resolution bandwidth: 500 Hz
• Sweep time: 5 ms
• Reference clock source: External
5. Use the spectrum analyzer to measure the mean output power of image
using the following spectrum analyzer parameter settings:
• Center frequency: frequency in step 3 – offset in step 3
• Reference level: +5 dBm
•Frequencyspan:0Hz
• Resolution bandwidth: 500 Hz
2,500 to 5,500 –46 –44
5,500 to 6,600 –43 –41
Table 5. Modulation Impairments Verification Upper Test Limits
LO Frequency
(MHz)
ISR (dBc)
Test Limit
CSR (dBc)
Test Limit

NI PXIe-5611 Calibration Procedure 16 ni.com
• Sweep time: 5 ms
• Reference clock source: External
6. Calculate the ISR according to the following formula and save the
values:
ISR = Measured Image Power – Measured RF Output Power
7. Repeat steps 3 through 6 for every offset frequency from –50 MHz to
+50 MHz in 5 MHz increments while keeping the LO frequency fixed.
Tip Set the NI-RFSG Generation Mode property to CW to generate a 0 Hz offset. The ISR
with a 0 Hz frequency offset cannot be measured, and the 0 Hz data point can be ignored.
8. Calculate the relative modulation bandwidth flatness by subtracting
the RF output power measured at 0 Hz offset from the RF output
powers measured at each of the other offset frequencies.
9. Compare each value calculated in step 8 to the limits in Table 6 and
compare only the ISR values calculated for offset frequencies between
–10 MHz and 10 MHz in step 5 to the limits in Table 7.
Note Values calculated for offset frequencies less than –10 MHz and greater than 10 MHz
are not specified and do not have test limits.
10. Repeat steps 3 through 9 for each LO frequency in Table 6.
Table 6. Modulation Bandwidth Impairment Verification Test Limits
LO Frequency
(GHz)
Modulation Bandwidth Test Limits (dB)
Maximum Minimum
0.2 3 –3
2.4 3 –3
4.0 3 –3
5.8 3 –3

©National Instruments Corporation 17 NI PXIe-5611 Calibration Procedure
If the results are within the selected test limit, the device has passed this
portion of the verification.
Verifying RF Path Gain
Complete the following steps to verify the RF path gain of the NI 5611
using a power meter, rubidium frequency standard, spectrum analyzer,
power splitter, and 6 dB attenuator.
Note The attenuator is placed in front of the spectrum analyzer to improve the spectrum
analyzer return loss. The power splitter must be characterized so that you can account for
its loss. Refer to the Characterizing the Power Splitter section for more information about
how to characterize your power splitter.
Table 7. Modulation Bandwidth Impairment Verification Test Limits for
Offset Frequencies Between –10 MHz and +10 MHz
LO Frequency (GHz) Test Limits ISR (dBc)
0.2 –41
2.4 –48
4.0 –45
5.8 –41

NI PXIe-5611 Calibration Procedure 18 ni.com
Figure 3. Connecting Hardware to Verify RF Path Gain
1. Connect the input port of the power splitter to the NI 5611 RF OUT
front panel connector.
2. Connect the PXI Express chassis 10 MHz REF IN rear panel connector
to the spectrum analyzer 10 MHz REF OUT rear panel connector.
Caution The port used to connect the power splitter to the power sensor in step 8 of the
Characterizing the Power Splitter section must be the same port used to connect the power
splitter to the power meter in step 3 of this section.
1 NI 5450 Arbitrary Waveform Generator
2 Connection from NI PXI Express
REF IN Rear Panel Connector to
Spectrum Analyzer REF OUT Rear Panel Connector
3 NI 5611 I/Q Modulator
4 NI 5652 RF Signal Generator
5 Power Sensor
6 Power Splitter
7 Attenuator
8 Power Meter
9 Spectrum Analyzer
10 CH A Connector
11 RF INPUT Connector
134
7
5
8
10
2
11
6
92

©National Instruments Corporation 19 NI PXIe-5611 Calibration Procedure
3. Connect one available port of the power splitter to the power meter.
Caution The port used to connect the power splitter to the 6 dB attenuator in step 9 of the
Characterizing the Power Splitter section must be the same port used to connect the power
splitter to the power meter in step 4 of this section.
4. Connect one available port of the power splitter to the 6 dB attenuator.
5. Connect one available port of the 6 dB attenuator to the spectrum
analyzer RF INPUT front panel connector.
6. Disconnect the NI 5450 CLK IN front panel connector from the
NI 5652 REF IN/OUT front panel connector.
7. Generate a single-sideband tone with a +1 MHz offset from the carrier
with the following NI-RFSG property settings:
• Frequency (Hz): 85 MHz
• Power Level (dBm): 5 dBm
• Generation Mode: Arb Waveform
• Reference Clock Source: ClkIn
8. Use the power meter to measure power splitter-compensated output
power.
9. Repeat steps 7 through 8 for every frequency from 85 MHz to 6.6 GHz
in 20 MHz increments, including endpoints.
10. Set the NI-RFSG Power Level property to 0 dBm, and repeat steps 7
through 9.
11. Set the NI-RFSG Power Level property to –30 dBm, and repeat steps 7
through 9, measuring the power using both the power meter and
spectrum analyzer. Use the following parameter settings for the
spectrum analyzer:
• Center frequency: frequency in step 7 + 1 MHz
• Reference level: –30 dBm
•Frequencyspan:0Hz
• Resolution bandwidth: 500 Hz
• Sweep time: 20 ms
• Reference clock source: External
• Attenuation: 5 dB
• Preamplifier: On
12. Use the power meter measurements to calculate a correction for the
spectrum analyzer inaccuracies and attenuator loss.

NI PXIe-5611 Calibration Procedure 20 ni.com
13. Set the NI-RFSG Power Level property to –60 dBm, and repeat steps 7
through 9 using only the spectrum analyzer and its measured
correction to measure the power accuracy using the following
spectrum analyzer parameter settings:
• Center frequency: frequency in step 7 + 1 MHz
• Reference level: –30 dBm
•Frequencyspan:0Hz
• Resolution bandwidth: 500 Hz
• Sweep time: 20 ms
• Reference clock source: External
• Attenuation: 5 dB
• Preamplifier: On
14. Set the NI-RFSG Power Level property to –90 dBm and repeat steps 7
through 9 using only the spectrum analyzer and its measured
correction to measure the power accuracy using the following
spectrum analyzer parameter settings:
• Center frequency: frequency in step 7 + 1 MHz
• Reference level: –30 dBm
•Frequencyspan:0Hz
• Resolution bandwidth: 500 Hz
• Sweep time: 200 ms
• Reference clock source: External
• Attenuation: 5 dB
• Preamplifier: On
15. Compare the measured values from steps 7 through 14 to the
corresponding limits in Table 8.
If the results are within the selected test limit, the device has passed this
portion of the verification.
Table 8. RF Path Gain Verification Test Limits
Output Power (dBm) Power Accuracy Test Limits (dB)
5±0.75
0±0.75
–30 ±0.75
–60 ±0.75
–90 ±0.75