MODIFIED DECISION FEEDBACK EQUALIZER HAVING PARTIAL SYMBOL SPACE AND EQUALIZING METHOD THEREOF, CONCERNED WITH PERFORMING AN INITIALIZATION PROCESS WITHIN A SHORT PERIOD OF TIME

摘要

PURPOSE: A modified decision feedback equalizer having a partial symbol space and an equalizing method thereof are provided to perform an initialization process within a short period of time by using an MMSE method. CONSTITUTION: A coefficient of a feedback filter(410) is initialized by using a channel impulse response estimation value of a channel estimator(430). A coefficient of a feed-forward filter(420) is initialized by using PMMSE algorithm or MMSE algorithm. A post-cursor element is calculated by a feedback filtering process. An input signal of the second shift register of the feed-forward filter is stored. A feed-forward filtering process is performed. A sum of output values of the feed-forward filter is calculated. A sum of a polyphase feed-forward filter is obtained by summing up output values of the feed-forward filter. A transmission symbol is decided from multi-level QAM signals. The decided transmission symbol is stored into the first shift register and is outputted as an output of the equalizer.