A novel APP-based soft-output adaptive equalizer with enhanced channel tracking capability

A novel adaptive equalizer that exploits only the soft-information given by the a posteriori probabilities (APPs) of the states of the ISI channel for channel estimation, tracking and equalization is presented. Moreover, the channel tracking capability, of the receiver is enhanced by exploiting the knowledge of the power-delay profile of the link and, therefore, by taking into account an unequal distribution of the powers of the channel taps. This is done by modifying the channel estimator algorithm and by conveying into the covariance matrix of the channel estimation error the available information on the powers of the taps of the low pass equivalent sampled input-delay spread function