Deep neural network a posteriori probability detectors and media noise predictors for one- and two-dimensional magnetic recording

A method of noise detection and prediction for a hard disk drive (HDD), comprising:

• receiving at an equalizer, a plurality of hard disk drive readings that correspond to one or more coded bits configured as a vector r, wherein the one or more coded bits configured as the vector r includes a plurality of samples r(1), r(2) up to r(n);
• detecting a partial response equalized filtered output y(1) resulting from the received sample r(1) at a trellis-detector;
• wherein an intersymbol interference resulting from the partial response equalized filtered output y(1) is reduced and wherein a first block of coded bit log-likelihood ratios (LLRb) and a second block of coded bit log-likelihood ratios (LLRb) are outputted;
• iteratively decoding one or more error correction codes embedded in the second block of log-likelihood ratios (LLRb) so as to output a third block of log-likelihood ratios (LLR1);
• receiving at a deep neural network noise predictor, the first block of coded bit log-likelihood ratios (LLRb), the partial response equalized filtered output y(1), the third block of log-likelihood ratios (LLR1), and the one or more samples r(2) up to r(n), wherein the deep neural network noise predictor is configured to predict a media noise term of the partial response equalized filtered output y(1), and wherein the one or more samples r(2) up to r(n), the first block of coded bit log-likelihood ratios (LLRb) and the iteratively decoded second block of log-likelihood ratios (LLR1) improves estimation of the media noise and reduces a bit error rate (BER);
• and
• turbo equalizing through iteratively exchanging between the trellis-detector, the deep neural network noise predictor and a channel decoder in multiple passes so as to provide an improved media noise estimate ñm of the media noise, and wherein the trellis detector is configured to cancel the media noise after multiple iterations upon a converged bit error rate (BER).