# US 7,196,999 B2 · Method and apparatus for reproducing data and method and apparatus for recording and/or reproducing data > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,196,999 B2 - Document ID: US7196999B2 - Status: Granted - Kind: B2 - Application number: 09/814,379 - Filed: 2001-03-21 - Published: 2002-05-16 - Granted: 2007-03-27 - Earliest claimed: 2000-03-23 - Assignees: Sony Corporation - Inventors: Masayuki Hattori; Jun Murayama; Toshiyuki Miyauchi - Web page: https://patentgrep.com/patent/US7196999B2 ## CPC - H03M 13/6325: {Error control coding in combination with demodulation} - G11B 20/10009: {Improvement or modification of read or write signals} - G11B 20/1426: {conversion to or from block codes or representations thereof} - G11B 20/1866: {by interleaving (G11B20/1809 takes precedence)} - H03M 5/14: Code representation, e.g. transition, for a given bit cell depending on the information in one or more adjacent bit cells, e.g. delay modulation code, double density code - H03M 13/27: using interleaving techniques - H03M 13/2957: {Turbo codes and decoding} - H03M 13/2972: {Serial concatenation using convolutional component codes} - H03M 13/45: Soft decoding, i.e. using symbol reliability information (H03M13/41 takes precedence) - H03M 13/6343: {Error control coding in combination with techniques for partial response channels, e.g. recording} - G11B 2020/1434: {8 to 9 modulation} - G11B 2020/1446: {16 to 17 modulation} - H03M: CODING; DECODING; CODE CONVERSION IN GENERAL (using fluidic means F15C4/00; optical analogue/digital converters G02F7/00; coding, decoding or code conversion, specially adapted for particular applications, see the relevant subclasses, e.g. G01D, G01R, G06F, G06T, G09G, G10L, G11B, G11C, H04B, H04L, H04M, H04N; ciphering or deciphering for cryptography or other purposes involving the need for secrecy G09C) - G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R) ## Abstract A method and apparatus for recording or reproducing data in which high performance encoding and a high efficiency decoding are realized to lower the decoding error rate. A magnetic recording and/or reproducing apparatus 50 includes, in a recording system, a modulation encoder 52 for modulation encoding input data in a predetermined fashion and an interleaver 53 for interleaving data supplied from the modulation encoder 52 to re-array the data sequence. The magnetic recording and/or reproducing apparatus 50 also includes, in a reproducing system, a first deinterleaver for interleaving the input data for re-arraying the data sequence so that the bit sequence of data re-arrayed by the interleaver 53 will be restored to its original bit sequence, a modulation SISO decoder for modulation decoding data supplied from the first deinterleaver and a second deinterleaver for interleaving data corresponding to a difference value between data output by the modulation SISO decoder and data output by the first deinterleaver to re-array the data sequence of the difference data. ## Claims ### Claim 1 A data reproducing apparatus for reproducing data recorded by a recording equipment for recording data on a recording medium, the recording equipment including modulation encoding means for applying predetermined modulation encoding to input data, the input data having a bit sequence, wherein said modulation encoding means encodes the input data in accordance with a constraint condition by block modulation, and first interleaving means for interleaving data supplied from said modulation encoding means for re-arraying a data sequence corresponding to said data supplied from said modulation encoding means, said data reproduction apparatus comprising: deinterleaving means for deinterleaving reproduced data in a sequence such as to restore the data sequence to the bit sequence; modulation decoding means for modulation decoding data supplied from said deinterleaving means in conformance with said constraint condition, wherein said modulation decoding means includes likelihood calculating means for calculating a likelihood value corresponding to output codewords output by said modulation encoding means, wherein posterior probability information as a soft decision value for an input bit to said modulation encoding means and an output bit from said modulation encoding means is calculated using said likelihood value as calculated by said likelihood calculating means; and second interleaving means for interleaving difference data corresponding to a difference between data output by said modulation decoding means and data output by said deinterleaving means, based on the same interleaving position information as that of said first interleaving means, for re-arraying the sequence of the difference data. ### Claim 2 (depends on 1) The data reproducing apparatus according to claim 1, wherein said modulation decoding means is fed with a soft input signal and outputs a soft output signal. ### Claim 3 (depends on 1) The data reproducing apparatus according to claim 1, wherein said recording equipment includes precode means for filtering data supplied from said first interleaving means to compensate for channel characteristics, and the data reproducing apparatus further comprising: channel decoding means for decoding a channel response. ### Claim 4 (depends on 3) The data reproducing apparatus according to claim 3, wherein said channel decoding means is fed with a soft input signal and performs soft output decoding. ### Claim 5 (depends on 3) The data reproducing apparatus according to claim 3, wherein said channel decoding means is fed with a soft input signal and performs soft output decoding based on a trellis corresponding to the channel response. ### Claim 6 (depends on 4) The data reproducing apparatus according to claim 4, wherein said deinterleaving means interleaves data corresponding to a difference between data output by said channel decoding means and data output from said second interleaving means; and wherein said modulation decoding is iteratively performed between said modulation decoding means and said channel decoding means. ### Claim 7 (depends on 6) The data reproducing apparatus according to claim 6, wherein said recording equipment includes error correction encoding means for error correction encoding input data to supply data resulting from the error correction encoding to said modulation encoding means, and the data reproducing apparatus further comprises: error correcting soft decoding means for soft decoding an error correction code of the soft input signal corresponding to soft output data obtained by said modulation decoding means as a result of iterative decoding. ### Claim 8 (depends on 1) The data reproducing apparatus according to claim 1, wherein said first interleaving means interleaves data encoded by said modulation encoding means. ### Claim 9 (depends on 1) The data reproducing apparatus according to claim 1, wherein said modulation decoding means effects performs decoding based on a trellis corresponding to said constraint condition. ### Claim 10 (depends on 1) The data reproducing apparatus according to claim 1, wherein said first interleaving means interleaves data encoded with block modulation by said modulation encoding means in terms of a modulation encoding block as a unit. ### Claim 11 (depends on 1) The data reproducing apparatus according to claim 1, wherein said modulation encoding means encodes input data in accordance with said trellis conforming to said constraint condition; and said modulation decoding means performs decoding based on a trellis conforming to said constraint condition. ### Claim 12 (depends on 11) The data reproducing apparatus according to claim 11, wherein said first interleaving means interleaves data encoded by said modulation encoding means in terms of a modulation encoding block of said trellis as a unit. ### Claim 13 (depends on 2) The data reproducing apparatus according to claim 2, wherein said modulation decoding means performs soft output decoding based on the BCJR algorithm or on the SOVA algorithm. ### Claim 14 (depends on 1) The data reproducing apparatus according to claim 1, data is recorded on said recording medium by a magnetic, optical or magneto-optical system. ### Claim 15 A data reproducing method for reproducing data recorded by a recording method for recording data on a recording medium including a modulation encoding step of applying predetermined modulation encoding to input data having a bit sequence, encoding the input data in accordance with a constraint condition using block modulation, and a first interleaving step of interleaving data encoded in said modulation encoding step, for re-arraying a data sequence corresponding to said data encoded in said modulation encoding step, said data reproduction method comprising the steps of: deinterleaving the input data in a sequence such as to restore the data sequence to the bit sequence; modulation decoding data supplied from said step of deinterleaving, in conformance with said constraint condition, wherein the step of modulation decoding further includes a likelihood calculating step of calculating a likelihood value of output codewords generated and output by said modulation encoding step; calculating posterior probability information as a soft decision value for an input bit to said modulation encoding step and an output bit from said modulation encoding step using said likelihood value as calculated by said likelihood calculating step; and interleaving difference data corresponding to a difference between data decoded in said modulation encoding step and data re-arrayed in said step of deinterleaving, based on the same interleaving position information as that of said first interleaving step, for re-arraying the sequence of the difference data. ### Claim 16 (depends on 15) The data reproducing method according to claim 15, wherein said step of modulation decoding is fed with a soft input signal and outputs a soft output signal. ### Claim 17 (depends on 15) The data reproducing method according to claim 15, wherein said recording method includes a precode step of filtering data supplied from said first interleaving step to compensate for channel characteristics, and the data reproducing method further comprising: channel decoding a channel response. ### Claim 18 (depends on 17) The data reproducing method according to claim 17, wherein said step of channel decoding is fed with a soft input signal and performs soft output decoding. ### Claim 19 (depends on 17) The data reproducing method according to claim 17, wherein said step of channel decoding is fed with a soft input signal and performs soft output decoding based on a trellis corresponding to the channel response. ### Claim 20 (depends on 18) The data reproducing method according to claim 18, wherein said step of deinterleaving interleaves data corresponding to a difference between data decoded in said step of channel decoding and data re-arrayed in said step of interleaving; iteratively performing decoding between said step of modulation decoding and said step of channel decoding. ### Claim 21 (depends on 20) The data reproducing method according to claim 20, wherein said recording method includes an error correction encoding step of error correction encoding input data to supply data resulting from the error correction encoding to said modulation encoding step, and the data reproducing method further comprising: soft decoding an error correction code of the soft input signal corresponding to soft output data obtained by said modulation decoding step as a result of iterative decoding. ### Claim 22 (depends on 15) The data reproducing method according to claim 15, wherein said first interleaving step interleaves data encoded by said modulation encoding step so that the constraint condition is satisfied. ### Claim 23 (depends on 15) The data reproducing method according to claim 15, wherein said modulation decoding step effects performs decoding based on a trellis corresponding to said constraint condition. ### Claim 24 (depends on 15) The data reproducing method according to claim 15, wherein said first interleaving step interleaves data encoded with block modulation by said modulation encoding step in terms of a modulation encoding block as a unit. ### Claim 25 (depends on 15) The data reproducing method according to claim 15, wherein said modulation encoding step encodes input data in accordance with the trellis conforming to said constraint condition; and said step of modulation decoding performs decoding based on a trellis conforming to said constraint condition. ### Claim 26 (depends on 25) The data reproducing method according to claim 25, wherein said first interleaving step interleaves data encoded by said modulation encoding step in terms of a modulation encoding block of said trellis as a unit. ### Claim 27 (depends on 16) The data reproducing method according to claim 16, wherein said step of modulation decoding performs soft output decoding based on the BCJR algorithm or on the SOVA algorithm. ### Claim 28 (depends on 15) The data reproducing method according to claim 15, wherein data is recorded on said recording medium by a magnetic, optical or magneto-optical system. ### Claim 29 A data recording and reproducing apparatus for recording and reproducing data for a recording medium, said apparatus comprising: modulation encoding means for applying predetermined modulation encoding to input data having a bit sequence, wherein said modulation encoding means encodes the input data in accordance with a constraint condition by block modulation; first interleaving means for interleaving data supplied from said modulation encoding means for re-arraying a data sequence corresponding to said data supplied from said modulation encoding means; deinterleaving means for deinterleaving reproduced data in a sequence such as to restore the data sequence to the bit sequence; modulation decoding means for modulation decoding data supplied from said deinterleaving means in conformance with said constraint condition, wherein said modulation decoding means further includes: likelihood calculating means for calculating a likelihood value corresponding to output codewords output by said modulation encoding means, wherein posterior probability information as a soft decision value for an input bit to said modulation encoding means and an output bit from said modulation encoding means is calculated using said likelihood value as calculated by said likelihood calculating means; and second interleaving means for interleaving difference data corresponding to a difference between data output by said modulation decoding means and data output by said deinterleaving means, based on the same interleaving position information as that of said first interleaving means, for re-arraying the sequence of the difference data. ### Claim 30 (depends on 29) The data recording and reproducing apparatus according to claim 29, wherein said modulation decoding means is fed with a soft input signal and outputs a soft output signal. ### Claim 31 (depends on 29) The data recording and reproducing apparatus according to claim 29, further comprising: precode means for filtering data supplied from said first interleaving means to compensate for channel characteristics, and channel decoding means for decoding a channel response. ### Claim 32 (depends on 31) The data recording and reproducing apparatus according to claim 31, wherein said channel decoding means is fed with a soft input signal and performs soft output decoding. ### Claim 33 (depends on 31) The data recording and reproducing apparatus according to claim 31, wherein said channel decoding means is fed with a soft input signal and performs soft output decoding based on a trellis corresponding to the channel response. ### Claim 34 (depends on 32) The data recording and reproducing apparatus according to claim 32, wherein said deinterleaving means interleaves data corresponding to difference between the data output by said channel decoding means and data output from said second interleaving means; and wherein said modulation decoding is iteratively performed between said modulation decoding means and said channel decoding means. ### Claim 35 (depends on 34) The data recording and reproducing apparatus according to claim 34, further comprising: error correction encoding means for error correction encoding input data, wherein said modulation encoding means modulation encodes data supplied from said error correction encoding means; and error correcting soft decoding means for soft decoding an error correction code of the soft input signal corresponding to the soft output data obtained by said modulation decoding means as a result of iterative decoding. ### Claim 36 (depends on 29) The data recording and reproducing apparatus according to claim 29, wherein said first interleaving means interleaves data encoded by said modulation encoding means. ### Claim 37 (depends on 29) The data recording and reproducing apparatus according to claim 29, wherein said modulation decoding means performs decoding based on a trellis corresponding to said constraint condition. ### Claim 38 (depends on 29) The data recording and reproducing apparatus according to claim 29, wherein said first interleaving means interleaves data encoded with block modulation by said modulation encoding means in terms of a modulation encoding block as a unit. ### Claim 39 (depends on 29) The data recording and reproducing apparatus according to claim 29, wherein said modulation encoding means encodes input data in accordance with said trellis conforming to said constraint condition; and said modulation decoding means performs decoding based on a trellis conforming to said constraint condition. ### Claim 40 (depends on 39) The data recording and reproducing apparatus according to claim 39, wherein said first interleaving means interleaves data encoded by said modulation encoding means in terms of a modulation encoding block of said trellis as a unit. ### Claim 41 (depends on 30) The data recording and reproducing apparatus according to claim 30, wherein said modulation decoding means performs soft output decoding based on the BCJR algorithm or on the SOVA algorithm. ### Claim 42 (depends on 29) The data recording and reproducing apparatus according to claim 29, wherein data is recorded on said recording medium by a magnetic, optical or magneto-optical system. ### Claim 43 A data recording and reproducing method for recording and reproducing data for a recording medium, said method comprising the steps of: applying predetermined modulation encoding to input data having a bit sequence, wherein said modulation encoding encodes the input data in accordance with a constraint condition by block modulation; interleaving the modulation-encoded data for re-arraying a data sequence corresponding to the modulation-encoded data; deinterleaving reproduced data in a sequence such as to restore the data sequence to the bit sequence; modulation decoding the data supplied from said step of deinterleaving in accordance with said constraint condition, wherein said step of modulation decoding further includes a likelihood calculating step for calculating a likelihood value corresponding to each output codeword output by said modulation encoding step; calculating posterior probability information as a soft decision value for an input bit to said step of applying and an output bit from said step of applying using said likelihood value as calculated by said likelihood calculating step; and interleaving difference data corresponding to a difference between data decoded in said step of modulation decoding and data re-arrayed in said step of deinterleaving based on the same interleaving position information as that of said step of interleaving the modulation-encoded data. ### Claim 44 (depends on 43) The data recording and reproducing method according to claim 43, wherein said step of modulation decoding is fed with a soft input signal and outputs a soft output signal. ### Claim 45 (depends on 43) The data recording and reproducing method according to claim 43, further comprising: filtering data supplied from said step of interleaving the modulation-encoded data to compensate for channel characteristics, and channel decoding a channel response. ### Claim 46 (depends on 45) The data recording and reproducing method according to claim 45, wherein said step of channel decoding is fed with a soft input signal and performs soft output decoding. ### Claim 47 (depends on 45) The data recording and reproducing method according to claim 45, wherein said step of channel decoding is fed with a soft input signal and performs soft output decoding based on a trellis corresponding to the channel response. ### Claim 48 (depends on 47) The data recording and reproducing method according to claim 47, wherein said step of deinterleaving interleaves data corresponding to data between data output by said step of channel decoding and data output from said step of interleaving the difference data; and iteratively performs decoding between said step of modulation decoding and said step of channel decoding. ### Claim 49 (depends on 48) The data recording and reproducing method according to claim 48, further comprising: error correction encoding input data, wherein said step of applying modulation encodes data supplied from said step of error correction encoding; and soft decoding a error correction code of the soft input signal corresponding to soft output data obtained by said step of modulation decoding as a result of iterative decoding. ### Claim 50 (depends on 43) The data recording and reproducing method according to claim 43, wherein said step of interleaving the modulation-encoded data interleaves the modulation-encoded data so that the constraint condition is satisfied. ### Claim 51 (depends on 43) The data recording and reproducing method according to claim 43, wherein said step of modulation decoding performs decoding based on a trellis corresponding to said constraint condition. ### Claim 52 (depends on 43) The data recording and reproducing method according to claim 43, wherein said step of interleaving the modulation-encoded data interleaves the modulation-encoded data in terms of a modulation encoding block as a unit. ### Claim 53 (depends on 43) The data recording and reproducing method according to claim 43, wherein said step of applying modulation encodes input data in accordance with the trellis conforming to said constraint condition; and said step of modulation decoding performs decoding based on a trellis conforming to said constraint condition. ### Claim 54 (depends on 53) The data recording and reproducing method according to claim 53, wherein said step of interleaving the modulation-encoded data interleaves the modulation-encoded data in terms of a modulation encoding block of said trellis as a unit. ### Claim 55 (depends on 44) The data recording and reproducing method according to claim 44, wherein said modulation decoding step performs soft output decoding based on the BCJR algorithm or on the SOVA algorithm. ### Claim 56 (depends on 43) The data recording and reproducing method according to claim 43, wherein data is recorded on said recording medium by a magnetic, optical or magneto-optical system.