A simple parity check matrix LDPC code for perpendicular magnetic recording channels

In LDPC code design, the structure of code´s parity check matrix can be very crucial to code performance. In this paper, we have investigated a simple designed parity check matrix when the code is applied to a PMR channel of a storage system. Belief propagation algorithm and min-sum algorithm are two major decoding algorithms used to benchmarked the code´s merits. Additive white Gaussian noise channel (AWGN) and perpendicular magnetic recording (PMR) channel with SISO equalizer in PR2 target are the conditions of our investigation. The LDPC code itself is a modified array type. Its construction fairly simple compared to normal array and quasi-cyclic code. We used two decision variables to define the permutation matrix. A method proposed by Tanner´s et.al had been adapted to the modified array code. The decoders have been tested for 5 and 20. iterations. SNR versus BER and BLER were measured.