Digital Signal Processing Reference
In-Depth Information
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Figure 1.11
Laying the first transatlantic cable.
Tabl e 1 .1
The main transatlantic cables from 1858 to our day.
Cable
Year
Type
Signaling
Capacity
1858
Coax
telegraph
a few words per hour
1866
Coax
telegraph
6-8 words per minute
1928
Coax
telegraph
2500 characters per minute
TAT-1
1956
Coax
telephone
36
[
48 by 1978
]
voice channels
TAT-3
1963
Coax
telephone
138
[
276 by 1986
]
voice channels
TAT-5
1970
Coax
telephone
845
[
2112 by 1993
]
voice channels
TAT-6
1976
Coax
telephone
4000
[
10, 000 by 1994
]
voice channels
TAT-8
1988
Fiber
data
280 Mbit
/
s(
∼
40, 000 voice channels)
/
TAT-14
2000
Fiber
data
640 Gbit
s(
∼
9, 700, 000 voice channels)
logic; this enables the implementation of complex
data-dependent
com-
pression techniques and the inclusion of psychoperceptual models in order
to match the compression strategy to the characteristics of the human vi-
sual or auditory system. A music format such as mp3 is perhaps the first
example to come to mind but, as shown in Table 1.2, all communication do-
mains have been greatly enhanced by the gains in throughput enabled by
data compression.
