What is Bandwidth

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Bandwidth capacity refers to the range of frequencies. All frequencies are classified according to the electromagnetic spectrum and are measured in hertz (Hz). At one end, where frequencies are low, the spectrum includes radio and microwaves. In the middle, the spectrum is characterized by infrared radiation (IR), visible light, and ultraviolet (UV) radiation. High-frequency energy, such as X rays, gamma rays, and cosmic rays, occupies the other end of the spectrum. Within the radio spectrum, which is divided into eight segments ranging from extremely high frequency (EHF) to very low frequency (VLF), lies the communications spectrum.

This spectrum, which is important to communications satellites, is divided into ten parts. These arefrom the highest frequency to the lowestmillimeter (in the EHF range), W, V, Ka, K, Ku, X, C, S, and L (in the ultra-high-frequency, or UHF, range). A typical communications satellite in orbit today will have a series of bandwidth-specific transmitter-receiver units, called transponders, classified as C-band or Ku-band.