Investigation of graph-based detection in BPMR system with multi-track processing

A bit patterned media recording (BPMR) system is faced with two-dimensional (2-D) interference channel, that is inter-symbol interference (ISI) and inter-track interference (ITI), which degrades a performance of a magnetic recording system. In this paper, we propose two methods to modify message-passing in a factor graph to the graph-based (GB) detector in the 2-D interference channel. One applies the factor graph to the basic clusters in the cluster 2×2 channel matrix for the GB detector, while the second method the 2-D interference channel by ignoring cornered ITIs of the reliability updates in the factor graph to the basic clusters. The simulation results show the performance of the modified GB (MGB) detector (full) and MGB detector (no cornered ITIs) methods better than the conventional GB detector (full) on BPMR system at the areal density 2, 2.5 and 3 Tbits/in².