(d, k/T) Constrained Partial Response Maximum Likelihood Codes

• Main Authors: LI, Y. X., Subrahmanyam, J., DENG, Robert H.
• Format: text
• Language: English
• Published: Institutional Knowledge at Singapore Management University 1995
• Subjects: CODING theory; DECODERS (Electronics); Computer Sciences; Information Security
• Online Access: https://ink.library.smu.edu.sg/sis_research/162; http://dx.doi.org/10.1080/00207219508926136
• Institution: Singapore Management University

A new set of constrained codes, referred to as (d, k/l) constrained partial response maximum likelihood (PRML) codes, is proposed. These new constrained codes combine the benefits of both (d, k) run length limited codes and (0, k/l) PRML codes, with seemingly promising applications in PRML read channels for today's head/media combinations, using thin-film media and inductive read heads. The rules for generating any (d, k/l) code are presented, the Shannon capacity is tabulated for the codes of practical interest with d= 1 and 2, and the encoding finite state transition diagram and state-independent decoder are designed for a rate 1/2, (1, 7/6) code. Some differences among (d, k) codes, (0, k/l) codes, (0, k/l/M) codes and (d, k/l) codes are also addressed.