Page 334 - Schaum's Outline of Theory and Problems of Signals and Systems
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CHAP. 61 FOURIER ANALYSIS OF DISCRETE-TIME SIGNALS AND SYSTEMS
Changing the variable n = km on the right-hand side of the above expression, we obtain
Hence,
6.22. Consider the sequence x[n] defined by
In12
~[n]
=
otherwise
(a) Sketch x[n] and its Fourier transform X(R).
(b) Sketch the time-scaled sequence x(,jn] and its Fourier transform Xo,(R).
(c) Sketch the time-scaled sequence ~(~jn] its Fourier transform Xo,(R).
and
(a) Setting N, = 2 in Eq. (6.1331, we have
The sequence x[n] and its Fourier transform X(0) are sketched in Fig. 6-16(n).
Fig. 6-16
