Howtosignalprocessing
- Why do we use adaptive equalization?
- What are the two modes of operation for an adaptive equalizer?
- What are the characteristics of adaptive filters explain adaptive equalization in a digital communication system?
- Why does an equalizer that tracks the channel during data transmission still need to train periodically?
Why do we use adaptive equalization?
The adaptive equalizer aims to remove intersymbol interference caused by linear channel . Figure 4.15. Frequency response of channel.
What are the two modes of operation for an adaptive equalizer?
1. Decision Directed Mode: This means that the receiver decisions are used to generate the error signal. 2. Decision directed equalizer adjustment is effective in tracking slow variations in the channel response.
What are the characteristics of adaptive filters explain adaptive equalization in a digital communication system?
The adaptive filter contains a digital filter with adjustable coefficient(s) and the LMS algorithm to modify the value(s) of coefficient(s) for filtering each sample. The adaptive filter then produces an estimate of noise y(n), which will be subtracted from the corrupted signal d(n) = s(n) + n(n).
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.
