Low density parity check codes for magnetic recording channels

We propose a system for magnetic recording, using a low density parity check (LDPC) code as the error-correcting-code, in conjunction with a rate 16/17 quasi-maximum-transition-run channel code and a modified E/sup 2/PR4-equalized channel. Iterative decoding between the partial response channel and the LDPC code is performed. Simulations show that this system can achieve a 5.9 dB gain over uncoded EPR4. The algorithms used to design this LDPC code are also discussed.

[1]  W. Ryan.  Performance of high rate turbo codes on a PR4-equalized magnetic recording channel , 1998, ICC '98. 1998 IEEE International Conference on Communications. Conference Record. Affiliated with SUPERCOMM'98 (Cat. No.98CH36220).

[2]  David J. C. MacKay,et al.  Comparison of constructions of irregular Gallager codes , 1999, IEEE Trans. Commun..

[3]  Patrick Robertson,et al.  A comparison of optimal and sub-optimal MAP decoding algorithms operating in the log domain , 1995, Proceedings IEEE International Conference on Communications ICC '95.

[4]  Seiichi Mita,et al.  Turbo-EEPRML: An EEPR4 channel with an error-correcting post-processor designed for 16/17 rate quasi-MTR code , 1998, IEEE GLOBECOM 1998 (Cat. NO. 98CH36250).

[5]  A. Glavieux,et al.  Near Shannon limit error-correcting coding and decoding: Turbo-codes. 1 , 1993, Proceedings of ICC '93 - IEEE International Conference on Communications.

[6]  Alain Glavieux,et al.  Iterative correction of intersymbol interference : turbo-equalization : Iterative and Turbo decoding , 1995 .

[7]  A. Patapoutian,et al.  Signal-dependent autoregressive channel model , 1999, IEEE International Magnetics Conference.

[8]  David J. C. MacKay,et al.  Good Error-Correcting Codes Based on Very Sparse Matrices , 1997, IEEE Trans. Inf. Theory.

[9]  Robert G. Gallager,et al.  Low-density parity-check codes , 1962, IRE Trans. Inf. Theory.

[10]  Alain Glavieux,et al.  Iterative correction of intersymbol interference: Turbo-equalization , 1995, Eur. Trans. Telecommun..

[11]  Paul H. Siegel,et al.  Turbo decoding for PR4: parallel versus serial concatenation , 1999, 1999 IEEE International Conference on Communications (Cat. No. 99CH36311).

[12]  John Cocke,et al.  Optimal decoding of linear codes for minimizing symbol error rate (Corresp.) , 1974, IEEE Trans. Inf. Theory.

[13]  Jung-Fu Cheng,et al.  Turbo Decoding as an Instance of Pearl's "Belief Propagation" Algorithm , 1998, IEEE J. Sel. Areas Commun..

[14]  Radford M. Neal,et al.  Near Shannon limit performance of low density parity check codes , 1996 .