Reproducing method, reproducing apparatus, recording and reproducing apparatus, and magnetic recording medium
View Patent ↗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.
1. A method of reproducing an information signal recorded in a magnetic recording medium including a magnetic layer including hexagonal ferrite, the method comprising the steps of:
reproducing the information signal from the magnetic recording medium; and
effecting PR (1, a, b, c, d, e) ML signal processing under 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,
wherein, when an isolated inversion waveform is reproduced as the information signal, the isolated inversion reproduced waveform has asymmetry at a ratio γ (%), and 9.8≦γ≦60.
2. The method as claimed in claim 1 , wherein 0.4≦a≦1.3, −0.6≦b≦0.0, −1.1≦c≦−0.2, −1.0≦d≦−0.4, and −0.3≦e≦0.0.
3. The method as claimed in claim 2 , wherein the reproduced information signal shows a normalized line density K, and K≦5.0.
4. The method as claimed in claim 3 , wherein the hexagonal ferrite comprises barium ferrite.
5. The method as claimed in claim 2 , wherein the hexagonal ferrite comprises barium ferrite.
6. The method as claimed in claim 1 , wherein the reproduced information signal shows a normalized line density K, and K≦5.0.
7. The method as claimed in claim 6 , wherein the hexagonal ferrite comprises barium ferrite.
8. The method as claimed in claim 6 , wherein 2.0<K<5.0.
9. The method as claimed in claim 1 , wherein the hexagonal ferrite comprises barium ferrite.
10. The method as claimed in claim 1 , wherein, when an isolated inversion waveform is reproduced as the information signal, the isolated inversion reproduced waveform has asymmetry.
11. A reproducing apparatus for reproducing an information signal recorded in a magnetic recording medium including a magnetic layer including hexagonal ferrite, the apparatus comprising:
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,
wherein, when an isolated inversion waveform is reproduced as the information signal, the isolated inversion reproduced waveform has asymmetry at a ratio γ (%), and 9.8≦γ≦60.
12. The reproducing apparatus as claimed in claim 11 , wherein 0.4≦a≦1.3, −0.6≦b≦0.0, −1.1≦c≦−0.2, −1.0≦d≦−0.4, and −0.3≦e≦0.0.
13. The reproducing apparatus as claimed in claim 12 , wherein the hexagonal ferrite comprises barium ferrite.
14. The reproducing apparatus as claimed in claim 11 , wherein the hexagonal ferrite comprises barium ferrite.
15. A recording and reproducing apparatus comprises:
recording means for recording an information signal in a magnetic recording medium including a magnetic layer including hexagonal ferrite; and
reproducing means for reproducing the information signal recorded in the magnetic recording medium, the reproducing means comprising:
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 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,
wherein, when an isolated inversion waveform is reproduced as the information signal, the isolated inversion reproduced waveform has asymmetry at a ratio γ (%), and 9.8≦γ≦60.
16. The magnetic recording medium used in the recording and reproducing apparatus as claimed in claim 15 .
17. A method of reproducing an information signal recorded in a magnetic recording medium including a magnetic layer including hexagonal ferrite in-plane oriented or randomly oriented, vertically magnetized, the method comprising the steps of:
reproducing the information signal from the magnetic recording medium; and
effecting PR (1, a, b, c, d, e) ML signal processing under a condition that 0.4≦a<3.0, −0.6≦b<2.0, −2.0<c≦−3.0<d≦−0.4, and −1.0<e≦0.0,
wherein, when an isolated inversion waveform is reproduced as the information signal, the isolated inversion reproduced waveform has asymmetry at a ratio γ (%), and 9.8≦γ≦60.
18. A method of reproducing an information signal recorded in a magnetic recording medium including a magnetic layer including hexagonal ferrite, the method comprising the steps of:
reproducing the information signal from the magnetic recording medium; and
effecting PR (1, a, b, c, d, e) ML signal processing under 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,
wherein the reproduced information signal shows a normalized line density K, and 3.0<K≦5.0.