This article is about telecommunications signalling methods. For high-speed Internet access,
than another standard or usual signal (and the broader the band, the greater the capacity for traffic).
Different criteria for "broad" have been applied in different contexts and at different times. Its
Different criteria for "broad" have been applied in different contexts and at different times. Its
origin is in radio systems engineering, but became popularized after MediaOne adopted it as part of
a marketing campaign in 1996 to sell their high speed data access. The slogan was "This is Broadband.
This is the Way". The term has never been formally defined, even though it is used widely and has been
the subject of many policy debates, and the FCC "National Broadband Plan".
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[edit]In telecommunication
Broadband in telecommunications refers to a signaling method that includes or handles a relatively wide range
(or band) of frequencies, which may be divided into channels or frequency bins. Broadband is always a
relative term, understood according to its context. The wider (or broader) the bandwidth of a channel, the
greater the information-carrying capacity. In radio, for example, a very narrow-band signal will carry
Morse code;
Morse code;
a broader band will carry speech; a still broader band is required to carry music without losing the high
audio frequenciesrequired for realistic sound reproduction. A television antenna described as "broadband"
may
may
be capable of receiving a wide range of channels; while a single-frequency or Lo-VHF antenna is
"narrowband"
"narrowband"
since it only receives 1 to 5 channels. In data communications adigital modem will transmit a datarate of 56
kilobits per seconds (kbit/s) over a 4 kilohertz wide telephone line (narrowband or voiceband). However
when
when
that same line is converted to an non-loaded twisted-pair wire (no telephone filters), it becomes hundreds
of kilohertz wide (broadband) and can carry several megabits per second (ADSL).
[edit]In DSL
The various forms of digital subscriber line (DSL) services are broadband in the sense that digital information
is sent over a high-bandwidth channel. This channel is located above (i.e., at higher frequency than) the
[edit]In Ethernet
A baseband transmission sends one type of signal using a medium's full bandwidth, as in
data links, and has a high data rate itself, so is sometimes referred to as broadband. Ethernet provided over
cable modem is a
common alternative to DSL.
[edit]In power-line communication
Power lines have also been used for various types of data communication. Although some systems for remote
control are based onnarrowband signaling, modern high-speed systems use broadband signaling to
achieve very
achieve very
(up to 1 Gigabit/s) Local area network using existing home wiring (including power lines, but also phone lines
and coaxial cables).
Broadband Over Powerline (BPL) has been a subject of experimentation but not deployment.
[edit]In video
Broadband in analog video distribution is traditionally used to refer to systems such as cable television,
where the individual channels aremodulated on carriers at fixed frequencies.[2] In this context, baseband
is the term's antonym, referring to a single channel of analog video, typically in composite form with
However, broadband video in the context of streaming Internet video has come to mean video files that have
bitrates high enough to requirebroadband Internet access in order to view them.
[edit]See also
- BISDN
- Broadband Integrated Services Digital Network
- Full service broadband
- Broadband mapping in the United States
- Global broadband and innovations
- National broadband plans from around the world
- Mobile broadband
- Wireless broadband
- Ultra-wideband
- Wideband
- Narrowband
- Broadband universal service
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