the present invention concerns an apparatus and method for reducing the multiuser - interference of input signals . the apparatus in accordance with the present invention comprises a multivariate predictor and a decision quantizer , said multivariate predictor operating on interference signals η &# 39 ; provided by means for extracting interference signals , said interference signals η &# 39 ; being obtained from said input signals and output signals b which are available at an output of said decision quantizer and fed back from there to said means for extracting interference signals .