Performance of perpendicular magnetic recording with track squeeze using bidirectional pattern-dependent noise prediction detector

Abstract

In this study, we investigated the performance of perpendicular magnetic recording with squeezed tracks. Based on spinstand signals, we developed a signal generation module to generate the readback signals for tracks of various squeezed track width and bit length. To mitigate the drop in bit error rate (BER) as squeezed track width decreases, we implemented the bidirectional pattern-dependent noise prediction (BiPDNP) detector with low-density parity check codes. To improve the BiPDNP detector over earlier work, we modified the log-likelihood ratio computation. Our results show that our proposed BiPDNP detector improves the bit error rate, and allows smaller squeezed track width and smaller bit length for the same BER performance.