Patent ID: 6621863
Filing Date: 2003-09-16
Classification: H03H,H04L

Abstract:
An equalizing apparatus of the type having a digital filter filtering a received signal to correct channel distortion, a data decision unit receiving a filtered signal from the digital filter and generating a data signal from the filtered signal by selecting a closest matching data value from a plurality of data values predetermined according to a signal modulation method, an error signal generator receiving the filtered signal and the data signal and generating an error signal, and a coefficient updating unit updating filter coefficients in the digital filter according to the error signal, the error signal generator comprising:an amplitude error signal generator generating an amplitude error signal from said filtered signal and said data signal; a squared envelope error signal generator generating a squared envelope error signal from a squared envelope value of said filtered signal; a weighting coefficient calculation unit calculating a weighting coefficient from an absolute value of said amplitude error signal, according to a predetermined conversion function; an amplitude error signal weighting unit weighting said amplitude error signal according to a first fixed constant and said weighting coefficient to obtain a weighted amplitude error signal; a squared envelope error signal weighting unit weighting said squared envelope error signal according to a second fixed constant and said weighting coefficient to obtain a weighted squared envelope error signal; and an adder adding said weighted amplitude error signal and said weighted squared envelope error signal to obtain the error signal output by said error signal generator.