Patent ID: 6678317
Filing Date: 2004-01-13
Classification: H04L

Abstract:
An adaptive equalizer device comprising:an adaptive equalizer receiving a signal indicating a symbol, for filtering said signal indicating said symbol to adaptively remove intersymbol interference by selectively using one of a plurality of preset algorithms; and a rotation detecting circuit receiving an output signal from said adaptive equalizer, for detecting rotation of said symbol of said output signal, wherein said rotation detecting circuit comprises a symbol protrusion detecting portion receiving said output signal, for detecting whether said symbol of said output signal exceeds a predetermined reference value, and a rotation period detecting portion receiving the result detected by said symbol protrusion detecting portion, for detecting whether said detected result from said symbol protrusion detecting portion indicates that said symbol exceeds said reference value within a given period and outputting the result as said detected result of said rotation detecting circuit; wherein said adaptive equalizer receives the result detected by said rotation detecting circuit to select a CMA (Constant Modulus Algorithm) method of said plurality of preset algorithms when the symbol is rotating and to select a DD (Decision Directed) method of said plurality of preset algorithms when the symbol is not rotating.