Modifying Viterbi Algorithm to Mitigate Intertrack Interference in Bit-Patterned Media

Bit-patterned media are currently being investigated to obtain magnetic recording densities of 1 Tbit/in 2 and more. In bit-patterned media, the adjacent tracks may be as close as adjacent bits in a track resulting in significant intertrack interference (ITI). In this work, we propose a modified trellis for the Viterbi algorithm (VA) that can mitigate the effects of ITI. Simulation results show that the modified VA improves the bit error rate. Using a simple model for track misregistration (TMR), the performance of this modified VA in the presence of TMR is also investigated. Based on the simulation results, this modified VA also appears to be more tolerant to TMR than the conventional VA