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PXIe-5673 Calibration Procedure
Verifying Output Intermodulation Products
Complete the following steps to verify the output intermodulation (IMD) performance of an
PXIe-5673 using a spectrum analyzer. Complete this test for each iteration in Table 8.
1.
Connect the PXIe-5611 RF OUT front panel connector to the spectrum analyzer RF INPUT
front panel connector through the SMA(m)-to-SMA(m) cable.
2.
Connect the PXIe-5450 CLK IN front panel connector to any rubidium frequency reference
rear panel BNC connector through the BNC(m)-to-SMA(m) cable.
3.
Connect the PXIe-5450 CLK OUT front panel connector to the PXI-5650/5651/5652
REF IN/OUT front panel connector.
4.
Connect any available rubidium frequency reference rear panel BNC connector to the
spectrum analyzer REF IN rear panel connector through the BNC(m)-BNC(m) cable.
5.
Generate two single-sideband tones simultaneously at 2 MHz (
F
1
) offset from the carrier
and 2.3 MHz (
F
2
) offset from the carrier with the following niRFSG property settings:
•
Frequency (Hz): 85 MHz
•
Power Level (dBm): 0 dBm
•
Generation Mode: Arb Waveform
•
Power Level Type: Peak Power
•
Reference Clock Source: ClkIn
The power of each tone should be approximately -6 dBm.
6.
Set the output power for the given measurements in Table 8.
7.
Use the spectrum analyzer to measure the mean amplitude of the first fundamental tone.
Name this value
P
1
. For example, when the LO is set to 85 MHz, measure the first
fundamental signal power at 87 MHz (LO +
F
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
8.
Use the spectrum analyzer to measure the mean amplitude of the second fundamental tone.
Name this value
P
2
. For example, when the LO is set to 85 MHz, measure the second
fundamental signal powers at 87.3 MHz (LO +
F
2
). Use the following spectrum analyzer
parameter settings:
•
Center frequency: (Frequency in step 5) +
F
2
•
Reference level: 0 dBm
•
Frequency span: 0 Hz
