Iterated Viterbi detection methods for a 2-D bit patterned mediastorage

Abstract

In this paper, we studied the performance of the iterated Viterbi detection methods using the multi-track multi-head processing for a bit patterned media (BPM) channel with a two-dimensional interference consisting of inter-symbol interference (ISI) and inter-track interference (ITI). In each method, three Viterbi detectors are employed to process the three readback signals. In their trellises, the number of states is designed based on the ISI only. After the first iteration, the estimated output sequences are exchanged between the adjacent detectors as the ITI estimations and then used in the metric calculation of next iteration. When compared with other methods, the simulation results show that the proposed methods achieve significant gains. We also investigated the performance of the proposed methods for the BPM channel with different media noise levels. Finally, the computational complexity of all detectors is compared.