Abstract: Certain aspects of the present disclosure provide an efficiently decodable QC-LDPC code which is based on a base matrix, the base matrix being formed by columns and rows, the columns being dividable into one or more columns corresponding to punctured variable nodes and columns corresponding to non-punctured variable nodes. Apparatus at a transmitting side includes a encoder configured to encode a sequence of information bits based on the base matrix. Apparatus at a receiving side configured to receive a codeword in accordance with a radio technology across a wireless channel. The apparatus at the receiving side includes a decoder configured to decode the codeword based on the base matrix.

Abstract: A base matrix of a rate-adaptive irregular QC-LDPC code is provided, the base matrix being formed by columns and rows having entries representing circulant submatrices. The columns of the base matrix are divided into at least one or more higher weight first columns and lower weight second columns and the rows of the base matrix are divided into first high weight rows corresponding to the high rate mother code and second low weight rows corresponding to the extension part related to the lower rate codes. A first submatrix formed by an intersection of entries of the second columns and entries of the first and the second rows is divided into first quadratic submatrices, wherein at most one entry in each column of each first submatrix and/or at most one entry in each row of each first submatrix is labelled.

Abstract: Certain aspects of the present disclosure provide an efficiently decodable QC-LDPC code which is based on a base matrix, the base matrix being formed by columns and rows, the columns being dividable into one or more columns corresponding to punctured variable nodes and columns corresponding to non-punctured variable nodes. Apparatus at a transmitting side includes a encoder configured to encode a sequence of information bits based on the base matrix. Apparatus at a receiving side configured to receive a codeword in accordance with a radio technology across a wireless channel. The apparatus at the receiving side includes a decoder configured to decode the codeword based on the base matrix.

Abstract: Certain aspects of the present disclosure provide an efficiently decodable QC-LDPC code which is based on a base matrix, the base matrix being formed by columns and rows, the columns being dividable into one or more columns corresponding to punctured variable nodes and columns corresponding to non-punctured variable nodes. Apparatus at a transmitting side includes a encoder configured to encode a sequence of information bits based on the base matrix. Apparatus at a receiving side configured to receive a codeword in accordance with a radio technology across a wireless channel. The apparatus at the receiving side includes a decoder configured to decode the codeword based on the base matrix.

Abstract: Provided is a base matrix of a rate-adaptive irregular QC-LDPC code, the base matrix being formed by columns and rows having entries representing circulant submatrices. The columns of the base matrix are divided into at least one or more higher weight first columns and lower weight second columns and the rows of the base matrix are divided into first high weight rows corresponding to the high rate mother code and second low weight rows corresponding to the extension part related to the lower rate codes. A first submatrix formed by an intersection of entries of the second columns and entries of the first and the second rows is divided into first quadratic submatrices, wherein at most one entry in each column of each first submatrix and/or at most one entry in each row of each first submatrix is labelled.

Abstract: Certain aspects of the present disclosure provide an efficiently decodable QC-LDPC code which is based on a base matrix, the base matrix being formed by columns and rows, the columns being dividable into one or more columns corresponding to punctured variable nodes and columns corresponding to non-punctured variable nodes. Apparatus at a transmitting side includes a encoder configured to encode a sequence of information bits based on the base matrix. Apparatus at a receiving side configured to receive a codeword in accordance with a radio technology across a wireless channel. The apparatus at the receiving side includes a decoder configured to decode the codeword based on the base matrix.

Abstract: A receiver configured for use in a communication system, such as a magnetic recording channel, and having a soft-output channel detector provided with a soft-input/soft-output (SISO) modulation codec for parity bits of a block error-correction code. A transmitter of the communication system is configured to encode data by applying a modulation code to the parity bits that have been generated using the block error-correction code. The SISO modulation codec provides an interface between the soft-output channel detector and a parity-check decoder that enables decoding iterations between them in a manner that takes into account inter-bit correlations imposed by the modulation code. In some embodiments, the soft-output channel detector is configured to operate at a fractional rate and to process an input signal carrying non-binary symbols, and the parity-check decoder is configured to apply parity-check-based decoding that is based on a non-binary low-density parity-check code.

Abstract: A receiver configured for use in a communication system, such as a magnetic recording channel, and having a soft-output channel detector provided with a soft-input/soft-output (SISO) modulation codec for parity bits of a block error-correction code. A transmitter of the communication system is configured to encode data by applying a modulation code to the parity bits that have been generated using the block error-correction code. The SISO modulation codec provides an interface between the soft-output channel detector and a parity-check decoder that enables decoding iterations between them in a manner that takes into account inter-bit correlations imposed by the modulation code. In some embodiments, the soft-output channel detector is configured to operate at a fractional rate and to process an input signal carrying non-binary symbols, and the parity-check decoder is configured to apply parity-check-based decoding that is based on a non-binary low-density parity-check code.

Abstract: A communication system, such as a magnetic recording channel, configured to apply modulation coding to parity bits of a block error-correction code. An embodiment of the communication system may have a transmitter having two different modulation encoders, one configured to apply a first modulation code to information bits and the other configured to apply a second modulation code to the parity bits that have been generated from the information bits using a block error-correction code. Alternatively or in addition, an embodiment of the communication system may have a receiver that incorporates a soft modulation codec configured to use the second modulation code in the log-likelihood-ratio space to enable decoding iterations between a sequence detector and a parity-check decoder.