Device and signal processing circuit for magnetic recording, magnetic recording apparatus
View Patent ↗A magnetic recording/reproducing apparatus includes a partial-response equalization circuit having frequency characteristic of cutting off low-frequency signal components inclusive of DC components; and a maximum-likelihood decoder, in which a reproduced signal outputted from the reproducing head is processed by the partial-response equalization circuit and then inputted into the maximum-likelihood decoder to be data-reproduced, thereby reducing a noise and distortion on the reproduced signal and reducing a data detection error rate.
1. A signal processing unit for a perpendicular magnetic recording/reproducing apparatus, comprising:
a partial-response equalization unit including a (1, 0, −1) equalizer unit and a partial-response interference value adding unit, wherein the (1, 0, −1) equalizer unit and the partial-response interference value adding unit perform a two-stage waveform process;
an equalization-adaptation unit; and,
an equalization-adaptation learning unit to monitor an output of the (1, 0, −1) equalizer unit, and responsive thereto, to produce an equalization-adaptation learning signal for application to the equalization-adaptation unit.
2. A signal processing unit as claimed in claim 1 , comprising:
an analog-to-digital converter unit; and,
a sample-timing control unit to monitor an output of the (1, 0, −1) equalizer unit, and responsive thereto, to produce a sample-timing control signal for application to the analog-to-digital converter unit.
3. A signal processing unit as claimed in claim 1 , wherein the partial-response interference value adding unit comprises a transversal filter with a fixed tap.
4. A signal processing unit as claimed in claim 1 , wherein the (1, 0, −1) equalizer unit shapes an incoming waveform into a short-bit waveform having an intersymbol interference (1, 0, −1) of a predetermined partial-response class.
5. A signal processing unit for a perpendicular magnetic recording/reproducing apparatus, comprising:
a partial-response equalization means including a (1, 0, −1) equalizer means and a partial-response interference value adding means, wherein the (1, 0, −1) equalizer means and the partial-response interference value adding means for performing a two-stage waveform process;
an epualization-adaptation unit; and,
an equalization-adaptation learning unit to monitor an output of the (1, 0, −1) equalizer means, and responsive thereto, to produce an equalization-adaptation learning signal for application to the equalization-adaptation unit.
6. A signal processing unit as claimed in claim 5 , comprising:
an analog-to-digital converter unit; and,
a sample-timing control unit to monitor an output of the (1, 0, −1) equalizer means, and responsive thereto, to produce a sample-timing control signal for application to the analog-to-digital converter unit.
7. A signal processing unit as claimed in claim 5 , wherein the partial-response interference value adding means comprises a transversal filter with a fixed tap.
8. A signal processing unit as claimed in claim 5 , wherein the (1, 0, −1) equalizer means is for shaping an incoming waveform into a short-bit waveform having an intersymbol interference (1, 0, −1) of a predetermined partial-response class.
9. A magnetic recording/reproducing apparatus, comprising:
a recording/reproducing head to write/read to/from a magnetic recording/reproducing medium storing data using perpendicular magnetic recording/reproducing; and,
a signal processing unit including:
a partial-response equalization unit including a (1, 0, −1) equalizer unit and a partial-response interference value adding unit, wherein the (1, 0, −1) equalizer unit and the partial-response interference value adding unit perform a two-stage waveform process to a signal reproduced from the magnetic recording/reproducing medium.
10. A magnetic recording/reproducing apparatus as claimed in claim 9 , comprising:
an automatic gain amplifier unit; and,
an automatic gain control unit to monitor an output of the (1, 0, −1) equalizer unit, and responsive thereto, to produce an automatic gain control signal for application to the automatic gain amplifier unit.
11. A magnetic recording/reproducing apparatus as claimed in claim 9 , comprising:
an analog-to-digital converter unit; and,
a sample-timing control unit to monitor an output of the (1, 0, −1) equalizer unit, and responsive thereto, to produce a sample-timing control signal for application to the analog-to-digital converter unit.
12. A magnetic recording/reproducing apparatus as claimed in claim 9 , comprising:
an equalization-adaptation unit; and,
an equalization-adaptation learning unit to monitor an output of the (1, 0, −1) equalizer unit, and responsive thereto, to produce an equalization-adaptation learning signal for application to the equalization-adaptation unit.
13. A magnetic recording/reproducing apparatus as claimed in claim 9 , wherein the partial-response interference value adding unit comprises a transversal filter with a fixed tap.
14. A magnetic recording/reproducing apparatus as claimed in claim 9 , wherein the (1, 0, −1) equalizer unit shapes an incoming waveform into a short-bit waveform having an intersymbol interference (1, 0, −1) of a predetermined partial-response class.