Abstract: An objective of the present invention is to provide a decoder, a perpendicular magnetic recording and reproducing device, a receiving device, and a decoding method that are used for performing decoding resistant to burst errors such as a pole-erase phenomenon, where the burst errors do not have amplitude fluctuation, without the addition of a special code (redundant code) for detecting burst errors. The present invention is a decoder, a perpendicular magnetic recording and reproducing device, a receiving device, and a decoding method that perform a decoding process on an encoded data signal, wherein a parity check is performed on the encoded data signal that is encoded with a low density parity check code to output burst information.

Abstract: An objective of the present invention is to provide a decoder, a perpendicular magnetic recording and reproducing device, a receiving device, and a decoding method that are used for performing decoding resistant to burst errors such as a pole-erase phenomenon, where the burst errors do not have amplitude fluctuation, without the addition of a special code (redundant code) for detecting burst errors. The present invention is a decoder, a perpendicular magnetic recording and reproducing device, a receiving device, and a decoding method that perform a decoding process on an encoded data signal, wherein a parity check is performed on the encoded data signal that is encoded with a low density parity check code to output burst information.

Abstract: A recording and reproducing apparatus includes: a recording section for recording an information signal in a magnetic recording medium including a magnetic layer including hexagonal ferrite; a reproducing section for reproducing the information signal recorded in the magnetic recording medium, the reproducing section including: a reproducing head for reading the information signal from the magnetic recording medium; an equalizer for equalizing the information signal read from the magnetic recording medium, wherein a partial response of the information signal after equalization by the equalizer satisfies a condition that 0.4?a<3.0, ?0.6?b<2.0, ?2.0<c??0.2, ?3.0<d??0.4, and ?1.0<e?0.0. A corresponding reproducing method, a corresponding reproducing apparatus, and the magnetic recording medium are also disclosed.

Abstract: Provided are a method and apparatus for equalizing and demodulating an information signal recorded in a magnetic recording medium by a partial response signal processing system if an isolated reversion producing waveform reproduced from the magnetic recording medium indicates an asymmetry. The method and apparatus reproduce the information signal from a high recording density of the magnetic recording medium.

Abstract: A recording and reproducing apparatus includes: a recording section for recording an information signal in a magnetic recording medium in which a magnetic layer containing hexagonal ferrite is formed; and a reproducing section for reproducing the information signal recorded in the magnetic recording medium, the reproducing section including: a reproducing head for reading the information signal from the magnetic recording medium; and an equalizer for equalizing the information signal read from the magnetic recording medium, wherein in the equalized information signal, coefficients a, b, c, d of PR(1, a, b, c, d) meet conditions that 0.1?a<2.0, ?0.9?b<?0.0, ?2.0<c??0.3, and ?1.0<d??0.1. A corresponding reproducing method, a corresponding reproducing apparatus, and the magnetic recording medium are also disclosed.

Abstract: A recording and reproducing apparatus includes: a recording section for recording an information signal in a magnetic recording medium including a magnetic layer including hexagonal ferrite; a reproducing section for reproducing the information signal recorded in the magnetic recording medium, the reproducing section including: a reproducing head for reading the information signal from the magnetic recording medium; an equalizer for equalizing the information signal read from the magnetic recording medium, wherein a partial response of the information signal after equalization by the equalizer satisfies a condition that 0.4?a<3.0, ?0.6?b<2.0, ?2.0<c??0.2, ?3.0<d??0.4, and ?1.0<e?0.0. A corresponding reproducing method, a corresponding reproducing apparatus, and the magnetic recording medium are also disclosed.

Abstract: A recording and reproducing apparatus includes: a recording section for recording an information signal in a magnetic recording medium in which a magnetic layer containing hexagonal ferrite is formed; and a reproducing section for reproducing the information signal recorded in the magnetic recording medium, the reproducing section including: a reproducing head for reading the information signal from the magnetic recording medium; and an equalizer for equalizing the information signal read from the magnetic recording medium, wherein in the equalized information signal, coefficients a, b, c, d of PR(1, a, b, c, d) meet conditions that 0.1?a<2.0, ?0.9?b<?0.0, ?2.0<c??0.3, and ?1.0<d??0.1. A corresponding reproducing method, a corresponding reproducing apparatus, and the magnetic recording medium are also disclosed.

Abstract: The reproducing method and apparatus, and recording and reproducing apparatus equalize and demodulate an information signal under a condition that coefficient terms (1, a1, a2, . . . , am (m: 2n or 2n+1; n, an integer not less than 1)) of a partial response satisfy any of equations (1) and (2) in a case that ? comprises a waveform of ?>0 and indicates an asymmetry of an isolated reversion producing waveform reproduced from the magnetic recording medium; and under a condition that the coefficient items of the partial response satisfy any of equations (3) and (4) in a case that the ? comprises a waveform of ?<0, wherein the equations (1) to (4) are: in a case of PR (1, a1, a2, . . . , a2n), 1 + ? ? k = 1 n - 1 ? a k ? < ? ? k = n + 1 2 ? n ? a k ? ( 1 ) in a case of PR (1, a1, a2, . . . , a2n+1), 1 + ? ? k = 1 n ? a k ? < ? ? k = n + 1 2 ? n + 1 ? a k ? ( 2 ) in a case of PR (1, a1, a2, . . .

Abstract: A magneto-optical recording and reproducing apparatus achieving an improvement in high density recording and bit error correction rate. The magneto-optical recording and reproducing apparatus comprises coding and modulating means for (1,7) RLL encoding and then NRZI encoding a digital information series {A.sub.i }; recording and reproducing means for recording the encoded series {a.sub.i } to a magneto-optical recording medium, and reproducing an analog signal from the medium as elementary waveform sequence e(t) using an optical head; a transversal filter type waveform equalizer for waveform equalizing elementary waveform sequence e(t) by applying the transfer function (1+2D+2D.sup.2 +D.sup.3) of the PR(1,2,2,1) encoding method to the elementary waveform of the encoded sequences, where delay operators D have a delay time of the encoded sequence cell width T.sub.