Patent ID: 7385900
Filing Date: 2008-06-10
Classification: H04L

Abstract:
1. A reproducing apparatus comprising: first means for reproducing a signal of a run-length-limited code from a recording medium; a transversal filter for subjecting the signal reproduced by the first means to partial-response waveform equalization to generate an equalization-resultant signal, the partial-response waveform equalization depending on tap coefficients; second means for detecting whether or not the signal reproduced by the first means corresponds to a zero-cross point, and generating 0-point information in response to a result of said detecting; a first delay circuit responsive to the 0-point information generated by the second means for outputting at least four successive samples of the 0-point information; a second delay circuit responsive to the equalization-resultant signal generated by the transversal filter for outputting at least four successive samples of the equalization-resultant signal; a temporary decision device for calculating a temporary decision value of the equalization-resultant signal on the basis of a PR mode signal, an RLL mode signal, the successive samples of the 0-point information which are outputted from the first delay circuit, and the successive samples of the equalization-resultant signal which are outputted from the second delay circuit, the PR mode signal representing a type of the partial-response waveform equalization, the RLL mode signal representing a type of the run-length-limited code; third means for calculating a difference between the temporary decision value of the equalization-resultant signal and an actual value thereof, and generating an error signal in response to the calculated difference; and fourth means for controlling the tap coefficients of the transversal filter in response to the error signal generated by the third means; wherein the type of the partial-response waveform equalization is PR(a, b, b, b, a).