The Design of Protograph LDPC Codes for 2-D Magnetic Recording Channels

This paper investigates the performance of the protograph-based low-density parity-check (LDPC) codes for 2-D intersymbol interference (ISI) channels with magnetic recording density. The protograph LDPC codes have been shown to possess simple hardware implementation and excellent error performance over additive white Gaussian noise channels and over partial response channels. We propose a design scheme and construct two new protograph LDPC codes for 2-D ISI channel, with the help of extrinsic information transfer chart analysis and asymptotic ensemble weight distribution analysis. The theoretical analyses and simulated results show that the proposed codes outperform the previously optimized irregular LDPC code in both low- and high-SNR regions. Thus, the proposed codes are good alternatives compared with other error-correction codes for the use in magnetic recording systems.