Agilent Technologies 86038B, Руководство пользователя

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Agilent 86038B Photonic Dispersion and Loss Analyzer, Second Edition
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Figure 16 Managing noise in high-resolution measurements
The bottom half of Figure 16 shows three setup parameters that
can be adjusted to push our measurement back toward the low
noise, high repeatability side of the figure. We can increase the
number of samples taken at each wavelength in the stepped
mode or the number of points by reducing the wavelength
increment in swept mode, achieving a phase noise reduction
through the averaging of all of these phase samples. We can also
decrease the IF bandwidth. Finally, in extreme cases, we may
elect to repeat the measurements and average the traces to
reduce noise. These three noise control approaches all lengthen
the measurement time.
Selecting setup conditions for a new type of narrowband device
Identifying the best setup conditions is a process that should be
performed once before testing a new class of device. Once the
appropriate setup conditions are determined, they can be saved
and used for all future measurements of devices that have
similar characteristics.
The simplest approach is to use the 86038B's Quick Setup
feature, which provides two slider-type controls that in turn
adjust the setup parameters in a consistent way. You may wish
to start by choosing a relatively small wavelength increment and
setting the Quick Setup slider controls for less speed but more
resolution and sensitivity.