Digital Signal Processing Reference
In-Depth Information
Exercises on Chapter 6
Exercise 1
(a)
Select a sweep generator from the library of DASY
Lab
-circuits and try varying the
start and stop frequency and the sweep speed systematically.
(b)
What „trick“ makes it possible to increase the linear time sweep frequency?
Exercise 2
Discuss the concept of
instantaneous frequency
. Why does this word contain an
inconsistency?
Exercise 3
In order to measure the frequency response you plan to “sweep” the system. What do you
have to take into consideration in order not to measure nonsense?
Exercise 4
Modern test signals
(a)
Why does the
-pulse appear to be an ideal test signal from a theoretical point of
view but not from a practical point of view?
δ
(b)
You wish to measure the entire
transfer function
of a filter according to the absolute
value and phase. What do you have to take into account?
(c)
Describe a method of measuring the
normed
transfer function according to absolute
value and phase. Select the appropriate circuit from the library of the DASY
Lab
circuits and analyse the method.
(d)
Complete this process and represent the transfer function as a local curve in the
GAUSSian plane.
(e)
You are to construct the hardware of a test signal generator. In the case of which
signal is this easiest?
(f)
What problems are there with the step function as a test signal and how can they be
avoided?
(g)
How can test signals be generated which have a constant amplitude curve in any
specifically defined frequency range?
(h)
What advantages and disadvantages do the last mentioned test signals have?
(i)
What are the possible fields of application for burst signals as test signals?
(j)
What makes the noise signal so interesting as a test signal? And what makes it so
difficult?
(k)
Measure the correlation factor between two different noise signals and one and the
same noise signal. What correlation factors do you anticipate and which do you
measure? How does the correlation factor depend on the length of the noise signal?
What does the correlation factor represent in terms of
content
?
