A bit interleaver, a bit-interleaved coded modulation (BICM) device and a bit interleaving method are disclosed herein. The bit interleaver includes a first memory, a processor, and a second memory. The first memory stores a low-density parity check (LDPC) codeword having a length of 64800 and a code rate of 3/15. The processor generates an interleaved codeword by interleaving the LDPC codeword on a bit group basis. The size of the bit group corresponds to a parallel factor of the LDPC codeword. The second memory provides the interleaved codeword to a modulator for 64-symbol mapping.

A method for operating a storage controller includes receiving a first read command, performing a first read of data stored in a nonvolatile memory using a first read level and receiving a first read data, performing first error correction decoding of the first read data to determine whether the first error correction decoding succeeds, determining a second read level using a predetermined method, and determining a first soft decision offset value of the second read level, reading data stored in the nonvolatile memory using the determined second read level and the first soft decision offset value and receiving a first soft decision data, performing second error correction decoding of the first soft decision data to determine whether the second error correction decoding succeeds, and storing the second read level, a first method used to determine the second read level and the first soft decision offset value.

Provided are an encoding method and device, a decoding method and device, and a storage medium. The encoding method comprises: encoding an initial to-be-encoded bit sequence with a low density parity check code LDPC having a code rate R.sub.1, to obtain an encoded first bit sequence, where 0≤R.sub.1≤1; linearly combining at least two bit sequence segments in the first bit sequence to obtain a second bit sequence; and cascading the first bit sequence and the second bit sequence to obtain a target bit sequence having a code rate R.sub.2, where 0≤R.sub.2≤R.sub.1≤1.

A method and a device of selecting a base graph of a low-density parity-check code are provided. The method includes: acquiring a data information length and a channel coding rate of to-be-encoded data; determining a target base graph selection strategy according to the data information length and an information length range of a base graph; determining a target base graph for the to-be-encoded data according to the target base graph selection strategy and the channel coding rate.

The present application provides a data processing method, a data processing device, a decoder, a network device and a computer-readable storage medium. The data processing method includes: classifying log likelihood ratio (LLR) elements according to a modulation mode, a preset decoder quantization threshold and a signal-to-noise ratio, to obtain a classification result; extracting feature information of each category in the classification result; calculating to obtain a scale factor according to the feature information of each category; and scaling the LLR elements according to the scale factor.

An LDPC decoding method of a received signal including a plurality of received symbols is provided. A decoding apparatus selects a perturbation space in which perturbation is to be performed based on a code length of the received signal and a maximum number of perturbation rounds indicating a number of perturbation rounds that can be performed, and performs a perturbation round. The decoding apparatus performs perturbation on a corresponding received symbol among the plurality of received symbols in each perturbation round, and decodes the received signal on which the perturbation has been performed. The decoding apparatus determines that decoding is successful when there is a perturbation round in which a decoding result of the received signal satisfies a predetermined condition.

A storage device includes a storage controller, which is configured to receive a command generated by a first virtual machine, from a host, and a non-volatile memory device, which is configured to store first data for the command. The command includes one of a retain command, which is generated to command the storage controller to retain the first data in the non-volatile memory device, or an erase command, which is generated to command the storage controller to erase the first data from the non-volatile memory device, when access between the first virtual machine and the storage controller at least temporarily interrupted.

A method for operating a storage controller includes receiving a first read command, performing a first read of data stored in a nonvolatile memory using a first read level and receiving a first read data, performing first error correction decoding of the first read data to determine whether the first error correction decoding succeeds, determining a second read level using a predetermined method, and determining a first soft decision offset value of the second read level, reading data stored in the nonvolatile memory using the determined second read level and the first soft decision offset value and receiving a first soft decision data, performing second error correction decoding of the first soft decision data to determine whether the second error correction decoding succeeds, and storing the second read level, a first method used to determine the second read level and the first soft decision offset value.

The present disclosure relates to low-density parity-check (LDPC) encoding methods and apparatus. One example method includes encoding k information bits by using a submatrix of ((n−k)/Z+j) rows and (n/Z+j) columns at an upper left corner of a check matrix H based on a first transmission code rate R satisfying R=k/(n+j×Z), obtaining a first codeword including the k information bits and (n−k+j×Z) redundant bits, and sending the first codeword to a receive end.

A processing device in a memory sub-system determines a syndrome weight for a sense word read from a memory device and determines whether the syndrome weight for the sense word satisfies a threshold criterion. Responsive to the syndrome weight for the sense word satisfying a respective threshold criterion associated with a next iteration of a first decoding operation, bypassing the first decoding operation and initiating a second decoding operation for the sense word, wherein the second decoding operation has a higher error correction capability than the first decoding operation.