Filter weight estimation device with update at hsdsch symbol rate, for a symbol level equaliser

Abstract

A filter weight estimation device (D), for an equaliser of a communication receiver, comprises i) a tap delay line connected to N branches each comprising a descrambler (DS-DSN) and a despreader (DE-DEN), for despreading received signals, corresponding to one or more available multiplexed channels associated with different channelization codes, with a reference code equal to the sum of all the channelization codes associated to the available multiplexed channels, Ë) an adaptive filter (AF) comprising N input filter taps respectively connected to the N branches and a regression input and arranged to estimate the sum of the symbols outputted by the despreaders (DE-DEN) and associated to each available channel, said symbol sum constituting a pseudo-symbol estimate defining a reference symbol estimate (rs), and to implement a mechanism of a LMS type to deliver a chosen number of filter weights (fi), iË) a quantiser (SM) arranged to quantise the reference symbol estimate (rs) to estimate a desired reference symbol (d), and iv) an error computation module (AM) for subtracting the reference symbol estimate (rs) from the desired reference symbol (d) to output an error signal (e) feeding the regression input.