Carrierless Amplitude/Phase Modulation
<communications> (CAP) A design of Asymmetric Digital Subscriber Line
transceiver developed by Bell Labs. CAP was the first ADSL design to be
commercially deployed and, as of August 1996, was installed on more lines than
any other.
CAP is a variation of Quadrature Amplitude Modulation, the modulation used by
most existing modems in 1997. With CAP, the three channels (POTS, downstream
data and upstream data) are supported by splitting the frequency spectrum. Voice
occupies the standard 0-4 Khz frequency band, followed by the upstream channel
and the high-speed downstream channel.
(1997-10-08)
Nearby terms:
Carnegie Mellon University « carpal tunnel syndrome
« Carriage Return « Carrierless Amplitude/Phase
Modulation
» carrier scanner » carrier signal » Cartesian
coordinates
carrier scanner
<security> (Or "wardialer") A program which uses a modem to dial a series
of phone numbers (say, from 770-0000 to 770-9999), and keeps a log of what phone
numbers answer with a modem carrier. The results of such a search were generally
used by people looking to engage in random mischief in random machines.
Since the 1980s, wardialers have generally fallen into disuse, partly because of
easily available "caller ID" technology, partly because fax machines are now in
wide use and would often be logged as a carrier by a wardialer, and partly
because there are so many new and more interesting venues for computerised
mischief these days.
(1997-03-16)
Nearby terms:
carpal tunnel syndrome « Carriage Return «
Carrierless Amplitude/Phase Modulation « carrier
scanner » carrier signal » Cartesian coordinates
» Cartesian product
carrier signal
<communications> A continuous signal of a single frequency capable of
being modulated by a second, data-carrying signal. In radio communication, the
two common kinds of modulation are amplitude modulation and frequency
modulation.
(1995-03-01)
Nearby terms:
Carriage Return « Carrierless Amplitude/Phase
Modulation « carrier scanner « carrier signal
» Cartesian coordinates » Cartesian product » CAS
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