| Communications Toolbox | |
Equalize signal using an equalizer object
y = equalize(eqobj,x)
y = equalize(eqobj,x,trainsig)
[y,yd] = equalize(...)
[y,yd,e] = equalize(...)
y = equalize(eqobj,x) processes the baseband signal vector x with equalizer object eqobj and returns the equalized signal vector y. At the end of the process, eqobj contains updated state information such as equalizer weight values and input buffer values. To construct eqobj, use the lineareq or dfe function, as described in Using Adaptive Equalizer Functions and Objects. The equalize function assumes that the signal x is sampled at nsamp samples per symbol, where nsamp is the value of the nSampPerSym property of eqobj. For adaptive algorithms other than CMA, the equalizer adapts in decision-directed mode using a detector specified by the SigConst property of eqobj. The delay of the equalizer is (eqobj.RefTap-1)/eqobj.nSampPerSym, as described in Delays from Equalization.
If eqobj.ResetBeforeFiltering is 0, then equalize uses the existing state information in eqobj when starting the equalization operation. As a result, equalize(eqobj,[x1 x2]) is equivalent to [equalize(eqobj,x1) equalize(eqobj,x2)]. To reset eqobj manually, apply the reset function to eqobj.
If eqobj.ResetBeforeFiltering is 1, then equalize resets eqobj before starting the equalization operation, overwriting any previous state information in eqobj.
y = equalize(eqobj,x,trainsig) initially uses a training sequence to adapt the equalizer. After processing the training sequence, the equalizer adapts in decision-directed mode. The vector length of trainsig must be less than or equal to length(x)-(eqobj.RefTap-1)/eqobj.nSampPerSym.
[y,yd] = equalize(...) returns the vector yd of detected data symbols.
[y,yd,e] = equalize(...) returns the result of the error calculation described in Error Calculation. For adaptive algorithms other than CMA, e is the vector of errors between y and the reference signal, where the reference signal consists of the training sequence or detected symbols.
For examples that use this function, see Equalizing Using a Training Sequence, Example: Equalizing Multiple Times, Varying the Mode, and Example: Adaptive Equalization Within a Loop.
lms, signlms, normlms, varlms, rls, cma, lineareq, dfe, Equalizers
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