Adaptive auto-orthogonalising equalisation system in the discrete frequency domain, and equaliser for effecting the system.

摘要

The adaptive auto-orthogonalising equaliser in the discrete frequency domain comprises a filter with N cells operating by the overlap-save method, a decision element which assigns one of the possible levels to the filtered samples, and a control circuit which at each iteration varies the cell gains on the basis of the input samples, the output samples and the decided symbols, and which comprises an estimator (SA) for estimating the gradient of the mean square error, an estimator (SB) for estimating a matrix which modifies said gradient such that its direction always passes as close as possible to the minimum to be sought, a projector (Ps) for projecting said corrected gradient into a constraint region, and a circuit for adjusting the filter cell gain vector at each iteration.