O/E Module MN4765B OM
PN: 10410-00742 Rev. H
A-1
Appendix A — Supplemental
Information
A-1
Characterization Files
The MN4765B O/E Calibration Module can be used to calibrate an E/O
device, usually an external modulator, to be used in O/E measurements. The
following calibration procedure guides you through an E/O calibration and
produces an s2p file that represents the E/O standard:
1.
Perform a 12-term calibration over the frequency range of interest. Save
this calibration to a USB memory device.
2.
Press the
Measurement
key on the front panel.
•
For VectorStar VNAs, select
Perform Optical Measurements
button, then select
O/E Measurements.
•
For ShockLine VNAs, select
O/E-E/O
button, then select
O/E
Measurements
.
•
When asked to load the original cal file, select the calibration
that was saved in Step 1.
3.
After loading the VNA calibration, load the s2p file for the MN4765B.
4.
Connect the optical components together as shown in
. Apply bias to the photodiode and to the modulator before
turning on the laser.
5.
Connect the AC adapter to the MN4765B. Ensure that the calibration
module is powered up and that the yellow OPERATE LED is on.
6.
Turn the laser ON and adjust the polarization to achieve the maximum
signal level. To enhance the response and reduce the signal-to-noise
ratio, increase the laser’s power and the VNA averaging count, and
lower the I.F. bandwidth.
•
At this point, the laser is on maximum power. The S21
parameter should show an E/O response over the entire
frequency range of the calibration. The next steps will generate
the modulator’s s2p file.
7.
From the
Display
menu, set the
Trace Format
to display
Log Magnitude
and Phase
. From the
Response
menu select
S21
.