Agilent Technologies 86038B User Manual page 69

Agilent 86038B Photonic Dispersion and Loss Analyzer, Second Edition
Figure 14 Ripple Error Due to Sideband Separation
The graph shown in Figure 15
wavelength step and modulation frequency for measurement of
fine group delay ripple. To use the chart, follow these steps:
1 Enter the x-axis at the estimated period of group delay ripple
to be measured.
2 Draw a vertical line to the curve representing the desired
number of measurement samples per period of the group
delay ripple.
3 Draw a horizontal line to the left and right hand axes. Read
the wavelength step and the modulation frequency from the
left and right vertical axes, respectively.
To balance the limiting effects of both parameters, the chart in
Figure 15 assumes that the double-sided spectral width of the
RF modulation spectrum is identical to the wavelength
increment. Of course, in some measurement situations it may be
appropriate to take smaller wavelength steps than the chart
would suggest. For example, to over-sample, then post-smooth
the data to reduce trace noise. The 86038B provides built-in
smoothing functions for this purpose.
is an aid to selecting the
69