User`s guide

Vector Scope
5-514
•Each frame of frequency-domain data shares the same length as the frame
of time-domain data from which it was generated; for example, when the
FFT is computed on the same number of points as are contained in the
time-domain input.
•The sample period of the time-domain signal in the simulation is equal to the
period with which the physical signal was originally sampled.
•Consecutive frames containing the time-domain signal do not overlap each
other; that is, a particular signal sample does not appear in more than one
sequential frame.
In cases where not all of these conditions hold, you should specify the
appropriate value for the
Sample time of original time-series parameter.
The
Frequency units parameter specifies whether the frequency axis values
should be in units of
Hertz or rad/sec, and the Frequency range parameter
specifies the range of frequencies over which the magnitudes in the input
should be plotted. The available options are
[0..Fs/2], [-Fs/2..Fs/2], and [0..Fs],
where F
s
is the original time-domain signal’s sample frequency.
The Vector Scope block assumes that the input data spans the range [0,F
s
), as
does the output from an FFT. To plot over the range
[0..Fs/2] the scope
truncates the input vector leaving only the first half of the data, then plots
these remaining samples over half the frequency range. To plot over the range
[-Fs/2..Fs/2], the scope reorders the input vector elements such that the last
half of the data becomes the first half, and vice versa; then it relabels the x-axis
accordingly.
If the
Frequency units parameter specifies Hertz, the spacing between
frequency points is 1/(M
∗T
s
). For Frequency units of rad/sec, the spacing
between frequency points is 2π/(M
∗T
s
). The Amplitude scaling parameter
allows you to select
Magnitude or dB scaling along the y-axis.
Scope Properties
The Vector Scope block allows you to plot time-domain, frequency-domain, or
user-defined data, and adjust the frame span of the plot. Selecting the
Scope
Properties
check box displays the Input domain parameter, which specifies
the domain of the input data. In addition, for time-domain data, a
Time
display span parameter
allows you to specify the number of frames to be
displayed across the width of the scope window at any given time. For