Iterative Decoding Using Attenuated Extrinsic Information from Sum-Product Decoder for PMR Channel With Patterned Medium

An LDPC coding and iterative decoding system is studied in perpendicular magnetic recording (PMR) with a bit-patterned medium. We propose an iterative decoding scheme using attenuated extrinsic information from a sum-product decoder, and the bit error rate (BER) performance of the LDPC coding and iterative decoding system is evaluated by R/W computer simulations. It has been clarified that at an areal density of 1 Tbpsi the proposed system provides a jitter margin of the island edges of approximately 0.6% larger than the conventional system using (3, 18)-regular LDPC code