Applications of low-density parity-check codes to magneticrecording channels

We consider the use of high-rate low-density parity-check (LDPC) codes for magnetic recording. We design and evaluate the performance of a magnetic recording system, which uses an LDPC code as the error-correcting code, in conjunction with a rate 16/17 quasimaximum-transition-run (QMTR) channel code on a modified E² PR4 (ME²PR4)-equalized channel. Iterative decoding between the partial response channel and the LDPC code is performed. Simulations show that an additional four-dB gain over the QMTR code can be obtained by the LDPC code. The algorithms used to design this LDPC code are also discussed