Data reproduction method and apparatus
AssigneeFujitsu Limited
InventorsMasakazu Taguchi, Toru Fujiwara
Life of this patent
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Abstract
In a data reproduction method and apparatus of the present invention, a Viterbi detection unit is provided, the Viterbi detection unit having a plurality of detectors each providing a first partial response signal with a first constraint length from a first sequence of samples derived from a first readout signal. One of connection and disconnection of the plurality of detectors in the Viterbi detection unit is selected in response to a timing signal, wherein, when the connection of the plurality of detectors is selected, the Viterbi detection unit provides a second partial response signal with a second constraint length from a second sequence of samples derived from a second readout signal, the second constraint length being different from the first constraint length.
Claims10
A data reproduction apparatus which reproduces data from recorded data, comprising:
- a Viterbi detection unit having a plurality of detectors each providing a first partial response signal with a first constraint length alone;
- a sample transmission unit transmitting a plurality of sequences of samples to the plurality of detectors respectively;
- an expected value transmission unit transmitting a plurality of expected values to the plurality of detectors respectively;
- a connection unit connecting the plurality of detectors together to cause the Viterbi detection unit to provide a second partial response signal with a second constraint length different from the first constraint length;
- and
- a connection control unit controlling connection and disconnection of the plurality of detectors by the connection unit in response to a constraint length of the recorded data.
A data reproduction method which reproduces data from recorded data, comprising the steps of:
- providing a Viterbi detection unit having a plurality of detectors each providing a first partial response signal with a first constraint length alone;
- transmitting a plurality of sequences of samples to the plurality of detectors respectively;
- transmitting a plurality of expected values to the plurality of detectors respectively;
- connecting the plurality of detectors together to cause the Viterbi detection unit to provide a second partial response signal with a second constraint length different from the first constraint length;
- and
- controlling connection and disconnection of the plurality of detectors in response to a constraint length of the recorded data.
Dependencies are inferred from the claim text.