Apparatus, having a variable equalizer, for reproducing a digital signal from a record carrier

摘要

An arrangement for reproducing a digital signal from a track on a record carrier includes a read head for reading the signal from the track, and a variable equalizer adapted to equalizer transmission characteristics of a transmission path, including a recording channel up to the variable equalizer, in response to first and second control signals. The first control signal (HF) has a relation with high frequency losses in a magnitude transmission characteristic of the transmission path, and the second control signal (PHI) has a relation with a difference in delay caused by the transmission path between low frequency signals and high frequency signal in an operating frequency range of the transmission path. The variable equalizer has a finite impulse response filter unit, which includes a delay line unit having a number of N taps, a multiplier unit for multiplying a signal present at the n-th tap of the delay line unit by a multiplication factor a(n) and for supplying the multiplier signal to a signal combiner. The variable equalizer also has a multiplication factor generator unit for generating the multiplication factors a(n) in response to the first and second control signals.