Bandwidth
lastmod 2017-08-17created 2016-04-283 edits
Bandwidth (Hanja: 帶域幅; native Korean term: ttineobi) is the range of frequencies over which a particular function can be performed, measured in hertz. Bandwidth is treated as an important concept in many fields, including information theory, wireless communication, signal processing, and spectroscopy. According to the Shannon-Hartley theorem, the data rate of reliable communication is closely proportional to the frequency range of the signal used for the communication. The term bandwidth here refers to the data rate or the frequency range (or both) of a communication system. For example, in wireless communication, the frequency range occupied by a modulated carrier wave is called the bandwidth.
Bandwidth is a concept that is hard to define precisely in a single way, and is perceived as a vague concept indicating how wide a range a particular function operates over in the frequency domain. In other domains it is also defined as another (specific) concept. Systems, filters, and signals have bandwidth. The frequency range over which a system, filter, or signal operates can be defined as its bandwidth. Bandwidth does not refer to absolute frequency; it only indicates the occupied range.