National Instruments NI PXIe-5673E, Процедура калибровки

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18 | ni.com | PXIe-5673E Calibration Procedure
4. 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: RefIn
The power of each tone should be approximately -6 dBm.
5. Set the output power for given measurements in Table 8.
6. 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 4) +
F
1
• Reference level: 0 dBm
• Frequency span: 0 Hz
• Resolution bandwidth: 500 Hz
• Sweep time: 5 ms
• Reference clock source: External
7. 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 4) +
F
2
• 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 first close-in IMD tone at
86.7 MHz (LO + 2
F
1
-
F
2
). Name this value
I
1
. Use the following spectrum analyzer
parameter settings:
•
Center frequency: (Frequency in step 4) +
F
1
• Reference level: 0 dBm
• Frequency span: 0 Hz
• Resolution bandwidth: 500 Hz
• Sweep time: 5 ms
• Reference clock source: External