Keysight Technologies N4374B, Руководство пользователя

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Making Measurements
78
Keysight
N4374B Lightwave Component Analyzer, User’s Guide
4 Set the power of the Laser to be applied to the test circuit.
If you are using the external source input, enter the value for
the power emitted from the LCA optical output port. (Use an
external power meter, or the LCA power meter).
5 If you are running measurements in an unstable
environment, or need extra accuracy or long term stability,
make sure to select “EverySweep” or “Continuous” for
Modulator Optimization.
Please note, optimizing every sweep adds about 1 second to
each measurement.
“Continuous” modulator bias optimization uses a 10 KHz
pilot tone is applied to the signal. This improves the short
and long term signal stability of the modulator working
point.
The pilot tone will affect measurements with IFBW settings
of the network analyzer >1.5 kHz.
For IFBW settings of the network analyzer >3 kHz we
recommended you do not use “Continuous” modulator bias
optimization, Use "Every Sweep" or "Once" instead.
Not using “Continuous” modulator bias optimization affects
the accuracy of the internal transmitter calibration.
We recommend you include a “User Calibration” in your
setup (“User Calibration” on page 65) if you are not using
“Continuous” modulator bias optimization.
The system is calibrated with a default setting. You can
determine the default setting by going to the tools page,
choosing “Default”, and pressing “Run”.
6 If you have optical components, such as attenuators, fiber
optic cables or splitters, between the laser output and your
device under test, open and enable the Optical Path
Deembedding.
Here you can enter the parameters for the optical path