Tektronix OM4006D, Руководство пользователя

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Appendix E: Equivalent-Time (ET) oscilloscope operation
Procedure to Correct the relative X-Y gain (ET).
1. You must complete all of the above steps fi rst including CorrectX and
CorrectY.
2. Type CorrectXY in the separate Matlab Application Window.
3. Copy and paste the resulting pHyb statement before DispCalEllipses,
replacing any other pHyb statement.
4. Move the input fi ber until there is signal on all four channels.
5. Click Run . The green trace should now be circular in both Constellations.
Finish the hybrid calibration.
1. The pHyb statement in 3 is the fi nal output that is corrected for RX
X-polarization, I-Q gain and phase, RX Y-polarization, I-Q gain and phase,
and X-Y relative gain.
2. Replace the DispCalEllipses statement with CoreProcessingCommands for
normal operation. Keep the pHyb statement as it is correcting the calibration.
Laser linewidth factor.
Refer to information on modifying the default value of
Alpha. (See page 34.)
Receiver Equalization.
Receiver Equalization is a factory calibration. Digital
equalization is applied to the four channels of the OM4000 instrument to account
for the non-ideal frequency dependent response introduced by the coherent optical
receiver and the receiver radio frequency front end. Depending on the sampling
rate of the oscilloscope and the bandwidth of the OM4000 instrument, digital
equalization is applied so that the combined effect of the receiver and the digital
equalization
fi lter meet a speci fi ed reference response:
138 OM4000D Series Coherent Lightwave Signal Analyzer