Bandwidth
Bandwidth is a range of frequencies that can perform a specific function, measured in hertz. Bandwidth is an important concept in many fields such as information theory, wireless communication, signal processing, and spectroscopy. According to Schonhard Hartley theory, the data rate of reliable communication is closely proportional to the frequency range of the signal used for communication. The term bandwidth refers to the data rate or frequency range of a communication system. For example, in wireless communications, the modulated carrier is called the frequency band width. Bandwidth is a concept that is hardly precisely defined, and it is perceived as an ambiguous concept that indicates how broad a particular function operates in the frequency domain. In other areas, it is defined as another concept. Systems, filters, and signals have bandwidth. The frequency range over which the system, filter, and signal operate can be defined as bandwidth. Bandwidth does not refer to the absolute frequency, but rather to the occupied range.