Calibrating The Network Analyzer Before Measurements - Agilent Technologies N4373A User Manual

Calibrating the network analyzer before measurements

Agilent N4373A Lightwave Component Analyzer, First Edition
About measurements
• Always perform an electrical calibration of the network
analyzer or load an existing calibration file before making
measurements.
If you make a measurement without a calibration, you will
get an error message.
• Make a note of the channel for which you make the
electrical calibration.
Always use this channel when setting up and making the
optical, electro- optical and opto- electrical measurements.
• After completing the calibration, do not alter the test port
power, IF bandwidth, start frequency, stop frequency,
measurement point number or other settings.
You may get measurement errors if you change the
parameters.
Keep the following points in mind during network analyzer
electrical calibration.
• To improve the S/N ratio of measurements, increase the
power of the network analyzer test port, though not so
high as to cause distortion in E/O converter modulation
characteristics.
• Decreasing the IF bandwidth improves the S/N ratio of
the measurement. However, doing so increases the
calibration and measurement times, so a suitable IF
bandwidth should be selected.
• Apply appropriate averaging or smoothing.
Electrical calibration
Calibrate the network analyzer with a short open loss test (2
port SOLT) before you start using the Lightwave Component
Analyzer, or return to the electrical measurement mode, as
described in "Returning to Electrical Measurements on the
ENA" on page 53 to do the calibration.
Do the calibration using the network analyzer calibration kit
according to the instructions in the network analyzer user
guide and online help.
Making Measurements on the ENA
43