Howtosignalprocessing
- What is the purpose of channel equalization?
- What does an equalizer do to a signal?
- What is channel equalization in digital communication?
- Why does an equalizer that tracks the channel during data transmission still need to train periodically?
What is the purpose of channel equalization?
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.
What does an equalizer do to a signal?
An equalizer is a device that can alter the spectral content of a signal. This can be done with any circuit that has an adjustable frequency response, the most familiar being the tone controls on a home stereo set. These tone controls typically affect the amplitude in two frequency regions, the treble and bass.
What is channel equalization in digital communication?
In digital communications systems, data is transmitted from the transmitter to the receiver over a channel, which may be a cable or a wireless medium. Every physical channel adds some random noise to the transmitted signal, and so the received signal is a noisy version of the transmitted signal.
Why does an equalizer that tracks the channel during data transmission still need to train periodically?
Equalizers require periodic retraining in order to maintain effective ISI cancellation. Immediately following the training sequence, the user data is sent. equalizer tracks the changing channel and adjusts its filter characteristics over time.
