DTFT, DFT, ZT, and FFT
547
0
5
10
time index n
15
20
25
0
5
10
time index n
15
20
25
Amplitude
−1
0
1
2
Amplitude
−1
0
1
2
[IDFT of the products of the DFTs] versus n
[Direct convolution in the time domain] versus n
FIGURE 5.61
Plots of g(n) = IDFT of the products of DFT[h(n)] with DFT[f (n)], and time convolution of h(n) with f(n) of Example 5.14.
0
5
10
[Impulse response h(n)] versus n
[Input sequence f(n)] versus n
15
0
5
10
15
time index n
Amplitude
−0.5
0
0.5
1
Amplitude
−1
−0.5
0
0.5
1
FIGURE 5.60
Plots of f(n) and h(n) of Example 5.14.
CRC_47760_CH005.indd 547
CRC_47760_CH005.indd 547
7/23/2008 1:47:41 PM
7/23/2008 1:47:41 PM
547
0
5
10
time index n
15
20
25
0
5
10
time index n
15
20
25
Amplitude
−1
0
1
2
Amplitude
−1
0
1
2
[IDFT of the products of the DFTs] versus n
[Direct convolution in the time domain] versus n
FIGURE 5.61
Plots of g(n) = IDFT of the products of DFT[h(n)] with DFT[f (n)], and time convolution of h(n) with f(n) of Example 5.14.
0
5
10
[Impulse response h(n)] versus n
[Input sequence f(n)] versus n
15
0
5
10
15
time index n
Amplitude
−0.5
0
0.5
1
Amplitude
−1
−0.5
0
0.5
1
FIGURE 5.60
Plots of f(n) and h(n) of Example 5.14.
CRC_47760_CH005.indd 547
CRC_47760_CH005.indd 547
7/23/2008 1:47:41 PM
7/23/2008 1:47:41 PM