A Blind Adaptive Decision Feedback Equalizer using Error Feedback

摘要

PURPOSE: A blind adaptive decision feedback equalizer using error feedback is provided to improve channel equalizing performance by reducing correlation of error signals by using an error feedback filter. CONSTITUTION: An equalizing filter(140) updates tap coefficients to apply the updated tap coefficients to a channel, and is formed of a front filter(140a), a rear filter(140b), and an error feedback filter(140c) which are formed in parallel. The front filter filters signals received from a transmission channel. The rear filter removes interference between existing signals by using a decided signal. The error feedback filter feeds back errors or reducing correlation of the remaining errors. An adder(150) generates output of the equalizing filter. A judging unit(160) divides a waveform output through the adder into a real axis and an imaginary axis to judge signals for supplying the judged signals to the rear filter. An error function generator(210) receives complex signals output from the equalizing filter for obtaining an error function and supplying the error function to the equalizing filter.