Reduced complexity maximum likelihood sequence estimation for multitrack high-density magnetic recording channels

In this paper we investigate the problem of designing reduced complexity detectors for multitrack high-density magnetic recording systems. The detectors derived in this work operate on superstate sets and carry several survivors for each set. We show that such a reduced state increased survivor approach provides near optimal performance to the maximum likelihood method, namely the Viterbi Algorithm (VA), but operate at a fractional complexity of the VA.