Nortel Networks Corporation

Blackberry Corporation

Research in Motion Corporation

Muhammad Chaudhry

Michael Livshitz

Aleksandar Purkovic

Sergey Sukhobok

Nina K Burns

A method for constructing a low-density parity-check (LDPC) code using a structured base parity check matrix with permutation matrix, pseudo-permutation matrix, or zero matrix as constituent sub-matrices; and expanding the structured base parity check matrix into an expanded parity check matrix. A method for constructing a LDPC code using a structured base parity check matrix H=[H|H], His the data portion, and His the parity portion of the parity check matrix; the parity portion of the structured base parity check matrix is such so that when expanded, an inverse of the parity portion of the expanded parity check matrix is sparse; and expanding the structured base parity check matrix into an expanded parity check matrix. A method for encoding variable sized data by using the expanded LDPC code; and applying shortening, puncturing.System and method for operating a wireless device to encode data using low-density parity-check (LDPC) encoding is discussed. One example method includes: computing a number of modulated orthogonal frequency-division multiplexing (OFDM) symbols for transmitting the data; computing a number of shortening bits; distributing the number of shortening bits over the at least one LDPC codeword; computing a number of puncturing bits for the at least one LDPC codeword; distributing the number of puncturing bits over the at least one LDPC codeword; determining a criterion using at least one of the number of shortening bits and the number of puncturing bits; if the criterion is met, increasing the number of modulated OFDM symbols and recalculating the number of puncturing bits; generating the encoded data using the number of shortening bits, the number of puncturing bits, and the at least one LDPC codeword; and transmitting the encoded data.

Structured low-density parity-check (LDPC) code

A method for constructing a low-density parity-check (LDPC) code using a structured base parity check matrix with permutation matrix, pseudo-permutation matrix, or zero matrix as constituent sub-matrices; and expanding the structured base parity check matrix into an expanded parity check matrix. A method for constructing a LDPC code using a structured base parity check matrix H=[H|H], His the data portion, and His the parity portion of the parity check matrix; the parity portion of the structured base parity check matrix is such so that when expanded, an inverse of the parity portion of the expanded parity check matrix is sparse; and expanding the structured base parity check matrix into an expanded parity check matrix. A method for encoding variable sized data by using the expanded LDPC code; and applying shortening, puncturing.

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Gaithersburg, MD, United States of America

Muhammad Chaudhry