Digital Signal Processing Reference
In-Depth Information
Speaker
Recognition
Speaker Name
James Wilson
Speech Signal
FIGURE 1.3
Voice recognition system.
1.1.2
Discrete-Time Signals and Systems
One common factor in the applications listed above is the A/D conversion,
which will be discussed in detail in
Chapter 4
. However, the fundamental
operation in the A/D process is the process of sampling, as shown in
Figure 1.4. The continuous time signal
x
(
t
) is sampled uniformly at
T =
0.1 second to yield a
discrete-time signal x
(
nT
) or just
x
(
n
)
, N
1
≤
n
≤
N
2
.
Some
common examples of discrete-time signals are shown in
Figure 1.5
2
1
0
-1
-2
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
t, sec.
2
1
0
-1
-2
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
t, sec.
FIGURE 1.4
Sampling process with
T
= 0.1 s.
