Digital Signal Processing Reference
In-Depth Information
Exercise 2
Illustration 19:
Visualisation of measurement data
The
visualisation of measurement data and signal processes
is the most important aid in
this manuscript for understanding signal processes. DASY
Lab
provides many different
visualisation methods for measurement data and signal processes. First create the circuit
illustrated by means of various visualisation components (see above). Try to design the
size and position of the displays as on the screen. Select a sinusoidal signal with the
frequency f = 2 Hz.
(a)
Now start the system above left and watch all the displays for some length of time.
Try to find out which measurement data refer to the analogue instrument, the digital
instrument or the bar chart.
(b)
Try to see the correlation between the development of the signal on the screen of the
plotter and the measurement data on the list (f = 0,2 Hz). At what intervals are the
spot measurements of the signal ascertained or stored. How high is the so-called
sample rate with which "samples" of the course of the signal are taken?
(c)
For what kind of measurements are analog, digital instrument and bar graph
suitable? What measurement from a whole block sequence of measurements do
they reproduce?
(d)
Which of the "display instruments" most clearly provides the readings which the
computer could then process?
(e)
Find out how to set the block format and the sample frequency in the menu (A/D).
What exactly do these two quantities indicate?
(f)
Set a block format of 1024 and a sample frequency of 1024 for all further experi-
ments. How long does the recording of a measurement sequence (of a block) take
and how many readings does it consist of?
