Improved Data Recovery from Patterned Media With Inherent Jitter Noise Using Low-Density Parity-Check Codes

• Published in: IEEE transactions on magnetics Vol. 43; no. 10; pp. 3925 - 3929
• Main Authors: Ntokas, I.T., Nutter, P.W., Tjhai, C.J., Ahmed, M.Z.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.10.2007; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Bit error rate; Channels; Cross-disciplinary physics: materials science; rheology; Data recovery; Data storage; Degradation; Density; Exact sciences and technology; Fabrication; Geometry; Iterative decoding; Jitter; Lithography; Lithography jitter; low-density parity-check (LDPC) codes; Magnetic memory; Magnetism; Materials science; Media; Other topics in materials science; Parity check codes; Perpendicular magnetic recording; perpendicular patterned media; Physics; read channel performance; Waveforms; Lithography jitter; low-density parity-check (LDPC) codes; read channel performance; Density; perpendicular patterned media; Magnetic recording; Magnetic properties
• ISSN: 0018-9464; 1941-0069
• DOI: 10.1109/TMAG.2007.903349

Patterned magnetic media promises areal densities in excess of 1 Tbit/in 2 for data storage. However, current imperfect patterning techniques result in a variation in the dimensions and distribution of the fabricated islands. As a result, this variation introduces jitter in the replay waveform that makes data recovery difficult. In this paper, we investigate the use of low-density parity-check (LDPC) codes and iterative decoding for mitigating the effects of lithography jitter and improving the read channel performance in patterned media storage systems. In addition, we show that the adoption of LDPC coding techniques permits an increase in the data storage capability of the medium to approximately 1.6 Tbit/in 2 with acceptable bit-error-rate performance.