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-headprocessing 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 threereadback signals. In their trellises, the number of states is designed based on the ISI only. After the first iteration, the estimatedoutput sequences are exchanged between the adjacent detectors as the ITI estimations and then used in the metric calculationof next iteration. When compared with other methods, the simulation results show that the proposed methods achievesignificant gains. We also investigated the performance of the proposed methods for the BPM channel with different medianoise levels. Finally, the computational complexity of all detectors is compared.

Keywords

• inter-track interference
• inter-symbol interference
• bit patterned media storage
• multi-track detection
• Viterbi algorithm
• media noise