Keysight Technologies 86120B, User Manual

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Performance Tests
Test 5. Amplitude Accuracy and Linearity
Test 5. Amplitude Accuracy and Linearity
Equipment Amplitude linearity is performed using the following devices:
• 1550 nm DFB lasers
• Optical attenuator
• 11896A Polarization Controller
• Optical power meter
Procedure
1 Turn on the laser and allow it to warm up.
2 Connect the laser’s output to the optical attenuator’s input.
3 Connect the optical attenuator’s output to the polarization controller’s optical input.
4 Connect the polarization controller’s optical output to the optical power meter.
5 Configure the optical power meter for 1550 nm.
6 Adjust the optical attenuator so that the power meter measures a power level of 0
dBm.
7 Enter the attenuator setting and the measured power level in the first row of
Table 6-22 on page 6-228 . Be sure to enter these values into the “Attenuator Settings”
and “Power Meter Readings” columns.
8 Enter the measured power on the following line:
Pwr: ____________
9 Change the attenuator in 1 dB steps as shown in Table 6-22 , and enter the attenuator
settings and power measurements.
After completing this step, the first two columns of the table should be completely
Polarization sensitivity
To ensure measurement accuracy, minimize the movement of any fiber-optic
cables during this procedure. Moving cables causes polarization changes which
affect amplitude measurements.