AT&T 7500 series, 7100 series, 2500 series, 7200 series, 7400 series Analog-to-Digital Conversion

1-4TRANSMISSION TYPES

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_

1.Original signal

2. PAM pulses

3.0

1.4

6.2

1.3

2.8

5.9

4.1

Ts

3.PCM pulses

3

1

6

1

3

6

4

011 001 110 001 011 110 100

4.PCM output

011001110001011110100

Adapted from: Data and Computer Communications, by William Stallings, Macmillan Publishing Co., N.Y., 1988

Figure 1-1.Analog-to-Digital Conversion