Patent ID: 6298362
Filing Date: 2001-10-02
Classification: H03H,H04L

Abstract:
Apparatus for forming coefficient signals in an update unit of an adaptive equalizer filter, said apparatus responsive to error signals and a data signals having a plurality of signal levels, wherein non-zero, equal sign data signal levels differ from a neighboring data signal level by a factor of 2, said apparatus comprising:at least one shift unit for providing intermediate error signals, said intermediate errors signals having the same magnitudes as said data signal levels;a first selection unit for selecting intermediate error signals determined by logic signals representing a current data signal;a complementary unit for providing complementary intermediate error signals which are the complement of said intermediate error signals;a second selection unit responsive to said logic signals for selecting a second intermediate error signal from a one of said intermediate error signals and said complementary error signals;a delay line; andan adder unit, said adder unit adding second intermediate and delay line signals stored in said delay in response to a control signal representing at least a portion said logic signals representing a current data signal, an output signal of said adder unit replacing said delay line signals, said output signal of said adder unit providing said coefficient signal.