A method and apparatus is disclosed to overcome the effects of intersymbol interference
during data transmission. Overcoming the effects of intersymbol interference makes
possible higher data transmission rates for a given error rate. In one embodiment
a receiver-transmitter pair is configured with a precode filter at the transmit
side and a feed forward filter and a feedback filter at the receive side. Filter
coefficients are calculated to reduce the undesirable effects of the channel, such
as intersymbol interference. In one embodiment a training process occurs with the
feedforward filter and a feedback filter, such that the first N coefficients of
the feedback filter are set to zero. Thereafter, the coefficients of the feedforward
filter are subject to spectral factorization and separated into minimum phase roots
and maximum phase roots. The minimum phase roots comprise the precode filter coefficients
and the maximum phase roots are established as feedforward filter coefficients.