A soft decision audio decoding system for preserving audio continuity in a digital wireless audio receiver is provided that deduces the likelihood of errors in a received digital signal, based on generated hard bits and soft bits. The soft bits may be utilized by a soft audio decoder to determine whether the digital signal should be decoded or muted. The soft bits may be generated based on the detected point and a detected noise power, or by using a soft-output Viterbi algorithm. The value of the soft bits may indicate confidence in the strength of the hard bit generation. The soft decision audio decoding system may infer errors and decode perceptually acceptable audio without requiring error detection, as in conventional systems, as well as have low latency and improved granularity.

A method and apparatus for decoding are disclosed. The method includes receiving a first Forward Error Correction (FEC) block of read values, starting a hard-decode process in which a number of check node failures is identified and, during the hard-decode process comparing the identified number of check node failures to a decode threshold. When the identified number of check node failures is not greater than the decode threshold the hard-decode process is continued. When the identified number of check node failures is greater than the decode threshold, the method includes: stopping the hard-decode process prior to completion of the hard-decode process; generating output indicating that additional reads are required; receiving one or more additional FEC blocks of read values, mapping the first FEC block of read values and the additional FEC blocks of read values into soft-input values; and performing a soft-decode process on the soft-input values.

A deep neural network (DNN) media noise predictor configured for one-dimensional-magnetic (1DMR) recording or two-dimensional-magnetic (TDMR) is introduced. Such architectures are often combined with a trellis-based intersymbol interference (ISI) detection component in a turbo architecture to avoid the state explosion problem by separating the inter-symbol interference (ISI) detection and media noise estimation into two separate detectors and uses the turbo-principle to exchange information between them so as to address the modeling problem by way of training a DNN-based media noise estimators. Thus, beneficial aspects include a reduced bit-error rate (BER), an increased areal density, and a reduction in computational complexity and computational time.

The invention discloses an improved method and a receiving device of the Viterbi algorithm. The improved method is applicable for a Viterbi decoder that receives an output signal generated by a convolution code encoder processing an original signal. The convolution code encoder includes M registers and M is a positive integer greater than or equal to 2. The improved method includes the following steps. First, for the first to the Mth data of the output signal, the Viterbi decoder performs the add-compare-select operation based on the known M initial values of the M registers. Then, for the Mth-last to the last data of the output signal, the Viterbi decoder performs the add-compare-select operation based on the known last M bits values of the original signal, thereby reducing the computational complexity of the add-compare-select unit.

A soft decision audio decoding system for preserving audio continuity in a digital wireless audio receiver is provided that deduces the likelihood of errors in a received digital signal, based on generated hard bits and soft bits. The soft bits may be utilized by a soft audio decoder to determine whether the digital signal should be decoded or muted. The soft bits may be generated based on the detected point and a detected noise power, or by using a soft-output Viterbi algorithm. The value of the soft bits may indicate confidence in the strength of the hard bit generation. The soft decision audio decoding system may infer errors and decode perceptually acceptable audio without requiring error detection, as in conventional systems, as well as have low latency and improved granularity.

A data storage device is disclosed comprising a non-volatile storage medium (NVSM), wherein a plurality of codewords and corresponding parity sector are written to the NVSM and then read from the NVSM. Each codeword read from the NVSM is processed using a Viterbi-type detector, thereby generating codeword reliability metrics. The codeword reliability metrics for at least some of the codewords are processed using a low density parity check (LDPC) type decoder, thereby generating a LDPC reliability metric for each symbol of at least one codeword. The LDPC reliability metrics for at least one of an un-converged codeword are processed using the parity sector, thereby updating the un-converged codeword reliability metrics. Processing the codeword reliability metrics with the LDPC decoder and updating the reliability metrics with the parity sector is repeated at least once before updating the LDPC reliability metrics of at least the un-converged codeword using the Viterbi-type detector.

A data storage device is disclosed comprising a storage medium. Input data is encoded according to at least one channel code constraint to generate first data and second data. The first data is encoded into a first codeword, and the second data is encoded into a second codeword, wherein a first code rate of the first codeword is less than a second code rate of the second codeword. The first codeword and the second codeword are interleaved to generate an interleaved codeword, and the interleaved codeword is written to the storage medium.

Systems, methods, and apparatus are provided for iteratively decoding a codeword. Once a codeword is received, the codeword is processed to generate an incremental hard decision value and a log likelihood ratio amplitude value. These values are generated by processing the codeword using a soft output Viterbi algorithm. A faulty symbol in the codeword is identified. A complete hard decision value is generated using the incremental hard decision value. The LLR amplitude value and complete hard decision value corresponding to the identified faulty symbol are selectively provided to a decoder and the decoder uses these values to decode the codeword.

A data storage device is disclosed comprising a head actuated over a disk comprising a data track having at least a first data segment and a second data segment. A first plurality of codewords are generated, and a first parity sector is generated over the first plurality of codewords. The first plurality of codewords and the first parity sector are written to the first data segment. A second plurality of codewords are generated, and a second parity sector is generated over the second plurality of codewords. The second plurality of codewords and the second parity sector are written to the second data segment. During a read operation the data segments of the data track are processed sequentially to decode the codewords using a low density parity check (LDPC) decoder, wherein the reliability metrics of un-converged codewords are stored in a codeword buffer and updated using the respective parity sector.

The disclosed embodiments are directed to systems, devices, and methods for iterative message-passing decoding. In one embodiment, a method is disclosed comprising decoding a first codeword at a storage device using a detector and a decoder, the first codeword comprising a set of symbols from a first set of codewords; assigning, via the decoding, a set of confidence levels for each symbol in the first codeword; transmitting, by the storage device, the confidence levels to an iterative decoder; generating, by the iterative decoder, a second codeword based on the set of confidence levels, the second codeword excluding at least one symbol in the set of symbols; and iteratively decoding, by the iterative decoder, the second codeword using an erasure decoder; and transmitting, by the iterative decoder, soft information generated by the erasure decoder to the storage device for subsequent decoding by the storage device.