Tektronix OM4006D, User Manual

Page: 93 / 205

Taking measurements
Multicarrier spectrum.
The Multicarrier Spectrum plot is accessed by clicking on
the spectrum icon button on the Home tab. Right-click on the plot to select what
to display. By default the Input Signal spectrum is displayed. Each spectrum is
labeled with its channel number appearing at its center frequency.
Figure 7: Multicarrier spectrum context menu
Table 13: Multicarrier spectrum menu choices (right-click)
Item Description
Input signal Displays the power spectrum of the input signal in dBW.
After front-end
proc Displays the power spectrum after digital fi lter is applied as speci fi ed in
Analysis Parameters.
Front end fi lter Displays the digital fi lter transfer function speci fi ed in Analysis Parameters.
A control is provided to adjust where the plot is placed since the units
are relative, not dBW.
Subsequence
average Displays the power spectrum of the averaged signal as calculated by the
subsequence averaging function which is controlled by settings in Analysis
Parameters.
After FE proc,
X Poln Displays the power spectrum of the transmitter’s X-polarization signal
after front-end processing.
After FE proc,
Y Poln Displays the power spectrum of the transmitter’s Y-polarization signal after
front-end processing.
Multicarrier
channels Choose which of the multicarrier channels to display.
Show new
channels Automatically display any new channels which are added to the Multicarrier
channel list.
Save graphics
to PNG
fi le
Saves the current plot to a PNG fi le.
OM4000D Series Coherent Lightwave Signal Analyzer 69