Agilent Technologies 8719D, User Manual

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Windowing improves the dynamic range of a time domain measurement by the
frequency domain data prior to converting it to the time domain, producing an impulse
stimulus that has lower sidelobes This makes it much easier to see time domain responses that
are very different in magnitude. The reduction is achieved, however, at the expense of
increased impulse width. The effect of windowing on the step stimulus (low pass mode only) is
a reduction of overshoot and ringing at the expense of increased rise time.
the selection of three window types (see
6-10. Impulse Width, Level, and Windowing Values
window Low
Span -21 Span
Normal Span span
Maximum Span span
The mode simulates an impulse impulse width is twice of low pass
impulse width. The impulse levels are the same as low pass impulse levels.
Choose one of the three window shapes listed in 6-10. Or you can use the knob to select
any windowing pulse width (or rise time for a step stimulus) between the values. The
time domain stimulus levels depend only on the window selected.
is essentially no window. Consequently, it gives the highest
sidelobes.
(the preset mode) gives reduced sidelobes and is the mode
most often used.
window gives the minimum sidelobes, providing the
greatest dynamic range.
.
remembers a
step
rise time) different from the standard window values.
A window is activated only for viewing a time domain response, and does not affect a
displayed frequency domain response. 6-72 shows the typical effects of windowing on
the time domain response of a short circuit reflection measurement.
Appliwtion and Operation Concepts 6-131