Trellis-Based Detecting the Insertion and Deletion Bits for Bit-Patterned Media Recording

Bit-patterned media recording (BPMR) is one of the promising technologies for realizing an areal density up to 4 Tb/in2; however, it poses new challenges to read channel design, including the two-dimensional (2D) interference, media noise, and track mis-registration. Furthermore, the BPMR system encounters the insertion, deletion and substitution errors, which are primarily caused by mis-synchronization between the write clock and the island positions. In this paper, we propose a novel detection method that exploits the trellis structure to detect the occurrence of insertion/deletion bits. Specifically, the specific marker bits are inserted periodically inside an input data sequence before recording onto a magnetic medium. Hence, the branch metric calculation is monitored during the marker bits to determine if there is any insertion/deletion error in the system. Numerical results indicate that the proposed method can performs better than the conventional one in terms of the percentage of detection and the percentage of missed detection and false-alarm, especially at low signal-to-noise ratio scenario.