摘要:
Various embodiments of the present invention provide systems and methods for generating a code format. One method discussed includes: receiving a first matrix having a row width and a column height that is greater than one; incorporating a circulant into a first column of the first matrix; testing the first column for trapping sets, wherein at least one trapping set is identified; selecting a value to mitigate the identified trapping set; and augmenting the first matrix with a second matrix to yield a composite matrix. The second matrix has the selected value in the first column, and wherein the identified trapping set is mitigated.
摘要:
Various embodiments of the present invention provide systems and methods for format efficient data storage. As an example, a data storage device is described that includes: a storage medium, a read/write head assembly, and a read channel circuit. The read/write head assembly is disposed in relation to the storage medium and operable to sense information corresponding to an encoded codeword. The read channel circuit is operable to receive the encoded codeword. The read channel circuit includes a missing symbols insertion circuit, a codeword de-scramble circuit, an address insertion circuit, and a data decoder circuit. The missing symbols insertion circuit, the codeword de-scramble circuit, and the address insertion circuit together are operable to pad a derivative of the encoded codeword with a plurality of symbols, to de-scramble the derivative of the encoded codeword, and to insert address information corresponding to the derivative of the encoded codeword to yield a modified encoded codeword. The data decoder circuit is operable to apply a data decoding algorithm to the modified encoded codeword to yield a decoded output.
摘要:
Various embodiments of the present invention provide systems and methods for generating a code format. One method discussed includes: receiving a first matrix having a row width and a column height that is greater than one; incorporating a circulant into a first column of the first matrix; testing the first column for trapping sets, wherein at least one trapping set is identified; selecting a value to mitigate the identified trapping set; and augmenting the first matrix with a second matrix to yield a composite matrix. The second matrix has the selected value in the first column, and wherein the identified trapping set is mitigated.
摘要:
Techniques are provided that generate bit reliabilities for a detected sequence. A detector generates the detected sequence. According to one embodiment, a post-processor finds a first set of combinations of one or more error events in the detected sequence satisfying a complete set or a subset of error correction constraints corresponding to the first bit value, finds a second set of combinations of one or more error events in the detected sequence satisfying a complete set or a subset of error correction constraints corresponding to the second bit value, selects a first most likely combination of one or more events of the first set and a second most likely combination of one or more events of the second set, and generates a bit reliability based on the first and the second most likely values.
摘要:
A detector generates a detected sequence, and a post processor generates probability values that indicate the likelihood of a plurality of error events in the detected sequence. The post processor partitions the values into first and second subsets. The post processor selects a first most likely value from the first subset of the values and a second most likely value from the second subset of the values. The post processor generates a bit reliability based on the first and the second most likely values.
摘要:
Techniques are provided for iteratively decoding data recorded on a data storage device. An iterative decoder decodes the data using multiple decoding iterations to correct errors. In multiple iterations of the iterative decoder, a post processing block generates soft information, and a decoder applies a minimum sum decoding algorithm to a low density parity check (LDPC) code to generate extrinsic information based on the soft information and updated soft information.
摘要:
Techniques are provided for iteratively decoding data recorded on a data storage device. An iterative decoder decodes the data using multiple decoding iterations to correct errors. In multiple iterations of the iterative decoder, a post processing block generates soft information, and a decoder applies a minimum sum decoding algorithm to a low density parity check (LDPC) code to generate extrinsic information based on the soft information and updated soft information.
摘要:
Techniques are provided that generate bit reliabilities for a detected sequence. A detector generates the detected sequence. According to one embodiment, a post-processor finds a first set of combinations of one or more error events in the detected sequence satisfying a complete set or a subset of error correction constraints corresponding to the first bit value, finds a second set of combinations of one or more error events in the detected sequence satisfying a complete set or a subset of error correction constraints corresponding to the second bit value, selects a first most likely combination of one or more events of the first set and a second most likely combination of one or more events of the second set, and generates a bit reliability based on the first and the second most likely values.
摘要:
A detector generates a detected sequence, and a post processor generates probability values that indicate the likelihood of a plurality of error events in the detected sequence. The post processor partitions the values into first and second subsets. The post processor selects a first most likely value from the first subset of the values and a second most likely value from the second subset of the values. The post processor generates a bit reliability based on the first and the second most likely values.
摘要:
A layered LDPC decoder architecture includes a single MUX and a single shifter element for processing an optimized LDPC parity check matrix. The optimized LDPC parity check matrix may be a K×L sub-matrix having zero elements, non-zero elements defined by a circulant matrix or zero matrices, and identity matrixes.