Performance of dropout correction on real magnetic tape waveforms with dropouts

The need to increase both linear and track densities in tape recording tech nology calls for more robustness against dropouts, the sporadic losses in s ignal amplitude, that are a principal source of errors in tape systems. A d ropout correction scheme previously introduced by the authors enables more robust bit detection by restoring the signal afflicted by the dropout event . In this paper, we present the results of using this scheme on real oversa mpled waveforms from an experimental tape test stand. Real-time implementat ion using a peak detector has been simulated in this work. Albeit at a low density (1.85 channel bits per PW50), the emphasis of this study is to iden tify the types of error events caused by dropouts and to demonstrate the fe asibility of dropout compensation even in the case of very challenging drop outs presented by the experimental data set. It is shown that this scheme c an significantly reduce the frequency of dropout induced cycle slip error e vents that can be as long as the data block. In other cases, where cycle sl ip errors do not occur, the number of errors associated with dropout events is reduced, on average, by a factor of more than 2, The sensitivity of the method to the envelope detection method is examined, and this is identifie d as an opportunity for significantly improving the performance of the sche me.