Apparatus for recording and regenerating data

An apparatus for recording and regenerating data, said apparatus comprising:

• a recording part iteratively recording the data at a data unit dividing the data by a predetermined data length by sequentially changing a predetermined numbers of recording areas on a recording medium;
• a plurality of storage sample value storing parts corresponding to the predetermined numbers of recording areas, respectively, each storage sample value storing part storing a sample value obtained by sampling a regenerative signal from the data recorded on each recording area at the data unit;
• a plurality of pass metric calculating parts corresponding to said plurality of storage sample value storing parts, respectively, each pass metric calculating part calculating a branch metric and a pass metric based on each sample value;
• a plurality of likelihood converting parts corresponding to said plurality of pass metric calculating parts, respectively, each likelihood converting part converting a calculation result obtained by each said pass metric calculating part into likelihood of the calculation result,
• wherein each said pass metric calculating part calculates the pass metric based on the likelihood converted by each said likelihood converting part and decodes the data recorded on the recording medium.

An apparatus for recording and regenerating data, said apparatus comprising:

• a recording part recording original data and interleaved data in that a data order of said original data is changed, on a recording medium;
• a sample storing part storing sample values obtained by sampling regenerative signals from the original data and from the interleaved data recorded in said recording part;
• a pass metric calculating part calculating a branch metric and a pass metric based on each of the sample values stored in said sample value storing part;
• and
• a likelihood converting part converting each calculation result obtained by said pass metric calculating part into likelihood of each said calculation result;
• and
• an order changing-back part changing back an data order of the likelihood based on the change of the data order by said recording part,
• wherein said pass metric calculating part calculates the pass metric based on the likelihood which data order is changed back by said order changing-back part and decodes the data recorded on the recording medium.

An apparatus for recording and regenerating data, said apparatus comprising:

• a recording part converting a first data to be regenerated into a second data in accordance with a predetermined operation and recording the second data;
• a first decoding part calculating a branch metric and a pass metric as a first calculation result for a sample data by sampling a regenerative signal from the second data recorded on the recording medium and decoding the second data based on the first calculation result;
• a first likelihood converting part converting the first calculation result into a first likelihood of the first calculation result, said first likelihood corresponding to the first data;
• a second decoding part generating a synthesized sample value for the first data by a synthesizing process based on the first likelihood, calculating the branch metric and the pass metric as a second calculation result based on the first likelihood, and decoding the second data based on the second calculation result;
• and
• a second likelihood converting part converting the second calculation result into a second likelihood of the second calculation result, said second likelihood corresponding to the second data,
• wherein said first decoding part calculates the pass metric based on the second likelihood converted by said second likelihood converting part, and one of the first data decoded by the second decoding part and the second data decoded by the first decoding part is output as a regenerated data.

An apparatus for recording and regenerating data, said apparatus comprising:

• a plurality of equalizing parts equalizing a regenerative signal from data recorded on a recording medium by different types of partial responses;
• a plurality of decoding parts corresponding to said plurality of equalizing parts, respectively, each decoding part generating likelihood of a sample value of a regenerative signal equalized by each of said plurality of equalizing parts, and decoding the sample value;
• and
• a decoded data deciding part deciding decoded data based on any one of decoding results by said plurality of decoding parts,
• wherein each of said plurality of decoding parts decodes the sample value by considering the likelihood generated by one of other decoding parts.