The received radio signal includes contributions from a plurality of channels multiplexed by respective spreading codes. A matched filter receiver is allocated to each multiplexed channel to estimate an impulse response of the channel and to provide first soft estimates of symbols transmitted on the channel. The first soft estimates provided by the matched filter receivers are processed to obtain a corrected soft estimate of at least one symbol transmitted on a channel. That processing includes subtracting from the first soft estimate of the symbol at least one term equal to the product of a decision value assigned to another symbol transmitted on another channel, determined from a soft estimate obtained previously for said other transmitted symbol, and a correlation between two generalized codes associated respectively with said symbol and with said other symbol. The generalized code associated with a symbol transmitted on a channel is a convolution of the estimated impulse response of said channel and Q samples of the spreading code of the channel which correspond to said symbol.