What is "bandwidth"

bandwidth \band"width`\ n. The maximum rate of information transfer (measured in bits/second) that can be carried by a communication channel. ``The bandwidth of an analog telephone line is less than 100 kilobits per second.''

1930, in electronics, from band (n.1) + width.

n. 1 The width, usually measured in hertz, of a frequency band. 2 Of a signal, the width of the smallest frequency band within which the signal can fit. 3 (context networking English) The rate of data flow in digital networks typically measured in bits per second. 4 (context informal English) The capacity, energy or time required.

n. a data transmission rate; the maximum amount of information (bits/second) that can be transmitted along a channel

Bandwidth is the difference between the upper and lower frequencies in a continuous set of frequencies. It is typically measured in hertz, and may sometimes refer to passband bandwidth, sometimes to baseband bandwidth, depending on context. Passband bandwidth is the difference between the upper and lower cutoff frequencies of, for example, a band-pass filter, a communication channel, or a signal spectrum. In the case of a low-pass filter or baseband signal, the bandwidth is equal to its upper cutoff frequency.

Bandwidth in hertz is a central concept in many fields, including electronics, information theory, digital communications, radio communications, signal processing, and spectroscopy and is one of the determinants of the capacity of a given communication channel.

A key characteristic of bandwidth is that any band of a given width can carry the same amount of information, regardless of where that band is located in the frequency spectrum. For example, a 3 kHz band can carry a telephone conversation whether that band is at baseband (as in a POTS telephone line) or modulated to some higher frequency.

Bandwidth was a Canadian radio program, which formerly aired on most CBC Radio One stations in Ontario on Saturday afternoons. The program, produced by CBO-FM in Ottawa, was broadcast in all Ontario markets except Toronto, where CBLA airs its own local production, Big City, Small World, in the same time slot. The program also formerly aired in Nunavut, where it was later replaced by The True North Concert Series.

Hosted by Meg Wilcox, the program was an arts and culture magazine which profiles the music scene in the province, including album reviews, interviews with musicians, and live concert performances. Amanda Putz was the program's original host, but took a sabbatical from 2006 to 2009 to work for Radio Television Hong Kong and CBC Radio 3. Later hosts included Alan Neal and Adam Saikaley.

The program's cancellation was announced in April 2014, as part of funding cuts to the CBC. Repeats continued to air in the program's old timeslot until the new program In the Key of C, hosted by Craig Norris from the studios of CBLA-FM-2 in Kitchener, was launched in the fall.

The producers of Bandwidth were also associated with Fuse, a concert series which aired across Canada on all three of CBC's radio networks.

See also CBC Radio One local programming.

In computing, bandwidth is the bit-rate of available or consumed information capacity expressed typically in metric multiples of bits per second. Variously, bandwidth may be characterized as network bandwidth, data bandwidth, or digital bandwidth.

This definition of bandwidth is in contrast to the field of signal processing, wireless communications, modem data transmission, digital communications, and electronics, in which bandwidth is used to refer to analog signal bandwidth measured in hertz, meaning the frequency range between lowest and highest attainable frequency while meeting a well-defined impairment level in signal power.

However, the actual bit rate that can be achieved depends not only on the signal bandwidth, but also on the noise on the channel.

Bandwidth has several related meanings:

• Bandwidth (signal processing) or analog bandwidth, frequency bandwidth or radio bandwidth: a measure of the width of a range of frequencies, measured in hertz
• Bandwidth (computing), the rate of data transfer, bit rate or throughput, measured in bits per second (bit/s)
• Spectral linewidth: the width of an atomic or molecular spectral line, measured in hertz

Bandwidth can also refer to:

• Bandwidth (linear algebra), the width of the non-zero terms around the diagonal of a matrix
• In statistics kernel density estimation, "bandwidth" describes the width of the convolution kernel used
• A normative expected range of linguistic behavior in language expectancy theory
• In business jargon, the resources needed to complete a task or project
• Bandwidth (radio program): A Canadian radio program
• Graph bandwidth, in graph theory
• Coherence bandwidth
• Power bandwidth