Improvement in Bit Error Rate With a Combination of a Rate-3/4 Modulation Code and Intertrack Interference Subtraction for Array-Reader-Based Magnetic Recording

To improve the bit-error-rate (BER) performance of an ultrahigh-density bit-patterned magnetic recording (BPMR) system, the intersymbol interference and intertrack interference (ITI) effects resulting from the reduction of spacing between bit islands in both along-track and across-track directions must be efficiently handled. Array-reader-based BPMR is considered a key technology for future magnetic recording due to its advantages, such as its diversity gain against noise and ITI cancellation. This letter proposes a three-reader, four-track system where a simple rate-3/4 two-dimensional (2-D) modulation code and a new ITI subtraction technique are used to improve recording system performance. Moreover, a 2-D Viterbi detector is modified in accordance with the ITI subtraction scheme, which leads to lower complexity and better BER performance. Simulations demonstrate improvement in performance gains under position and size fluctuation effects.