公开(公告)号：DE3485428D1

公开(公告)日：1992-02-20

申请号：DE3485428

申请日：1984-07-11

Applicant: IBM

Inventor： DOLIVO FRANCOIS BERNARD ,  UNGERBOECK GOTTFRIED ,  HOWELL THOMAS DAVID

IPC: G11B11/20 ,  G11B20/10 ,  H04L25/497

公开(公告)号：SG150594G

公开(公告)日：1995-03-17

申请号：SG150594

申请日：1994-10-17

Applicant: IBM

Inventor： DOLIVO FRANCOIS BERNARD ,  UNGERBOECK GOTTFRIED ,  HOWELL THOMAS DAVID

IPC: H04L25/03 ,  H04L25/08 ,  H04L25/497 ,  G11B11/20

Abstract: A maximum-likelihood sequence decoder is used with a partial-response signaling system for processing sequences of sampled values from a communication channel or recording device. The partial-response signals can be duobinary, dicode, or partial-response class-IV. The maximum-likelihood decoding for each sequence is based upon a two-state trellis. lnstead of two survivor metrics for the two states, only a difference metric is generated which is simpler but sufficient for the decoding process. The decoder comprises survivor metric determining circuitry (81...99) which, from each input sample (y n ) and a previous difference metric (DJ n - 3 ) determines a new difference metric (DJ n-1 ), two additional binary values (b + , b-) for the two survivor sequences, as well as a binary output value (b) for making a selection among the two survivor sequences.

公开(公告)号：HK138294A

公开(公告)日：1994-12-16

申请号：HK138294

申请日：1994-12-08

Applicant: IBM

Inventor： DOLLVO FRANCOIS BERNARD ,  UNGERBOECK GOTTFRIED ,  HOWELL THOMAS DAVID

IPC: H04L25/03 ,  H04L25/08 ,  H04L25/497 ,  G11B11/20 ,  G11B20/10

Abstract: A maximum-likelihood sequence decoder is used with a partial-response signaling system for processing sequences of sampled values from a communication channel or recording device. The partial-response signals can be duobinary, dicode, or partial-response class-IV. The maximum-likelihood decoding for each sequence is based upon a two-state trellis. lnstead of two survivor metrics for the two states, only a difference metric is generated which is simpler but sufficient for the decoding process. The decoder comprises survivor metric determining circuitry (81...99) which, from each input sample (y n ) and a previous difference metric (DJ n - 3 ) determines a new difference metric (DJ n-1 ), two additional binary values (b + , b-) for the two survivor sequences, as well as a binary output value (b) for making a selection among the two survivor sequences.