Broadband

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; a broader band will carry speech; a still broader band is required to carry music without losing the high audio frequencies required for realistic sound reproduction. A television antenna described as "broadband" may be capable of receiving a wide range of channels; while a single-frequency or Lo-VHF antenna is "narrowband" since it only receives 1 to 5 channels. In data communications a digital modem will transmit a datarate of 56 kilobits per seconds (kbit/s) over a 4 kilohertz wide telephone line (narrowband or voiceband). However 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).