Track Misregistration Prediction Scheme of Two-Track Reading with a Wide-Track Reader for Shingled Track Recording

To enhance the areal density (AD) of magnetic recording technology, shingled magnetic recording (SMR), which overlaps adjacent tracks, has been proposed and extensively studied. The strong intertrack interference (ITI) is a major difficulty that needs to be overcome. Therefore, the two-track reading with a wide-track reader for the shingled track recording technique achieves the clear amplitude in two-track recording due to the longer bit length of magnetization over the regular single-track reading. Track misregistration (TMR); however, is one of the key concerns in this technique that may deteriorate the system’s performance, which refers to the misalignment between the center of the read head and the desired track. To address this issue, this study proposes the TMR prediction scheme and detector with the utilization of an Expectation-Maximization (EM) algorithm to process the readback signals obtained from the wide-track reader. Simulation results indicate that, at an AD of 2.0 Tb/in², the EM-based TMR prediction method achieves strong prediction performance, while the EM-based data detector further enhances system performance by reducing the bit- error rate in shingled track recording systems.