In
telecommunication,
equalization is the reversal of distortion incurred by a signal transmitted through a
channel.
Equalizers are used to render the
frequency response—for instance of a telephone line—
flat from end-to-end. When a
channel has been equalized the
frequency domain attributes of the signal at the input are faithfully reproduced at the output. Telephones,
DSL lines and television cables use equalizers to prepare data signals for transmission.