Abstract: 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.

Abstract: A low-density parity-check (LDPC) code encoding method and a communication apparatus are described that provide increased redundant bits through retransmission in an IR-HARQ mechanism, so as to decrease a channel coding rate, and improve decoding performance of an LDPC code. A check matrix of the LDPC code is used as a basic matrix, and the basic matrix is extended to obtain a mother matrix compatible with a plurality of code rates. During LDPC encoding, a transmit device reads, from the mother matrix, a check matrix corresponding to a required code rate, and performs LDPC encoding on an information bit sequence based on the read check matrix. LDPC encoding is performed on the information bit sequence by using check matrices of different sizes, to obtain different quantities of redundant bits.

Abstract: A convolutional code rate matching method and a communication apparatus are provided. A puncturing pattern of a second codeword at a second code rate is obtained based on a puncturing pattern of a first codeword at a first code rate. A second puncturing location set of the second codeword is a subset of a first puncturing location set of the first codeword. When a transmit device decreases a code rate from the first code rate to the second code rate, a redundant bit is sent at a location of a complementary set of the second puncturing location set relative to the first puncturing location set. Compared with the first puncturing location set, the second puncturing location set may obtain more incremental redundant bits, to decrease a channel encoding rate. This can improve decoding performance of a convolutional code.

Abstract: Method and system method comprising encoding a source word to be transmitted in a data unit from a source station in a wireless network, generating a first OFDM symbol that carries a data segment corresponding to encoded bits of the source word, duplicating the first OFDM symbol to generate a second OFDM symbol that is a linear phase-rotated copy of the first OFDM symbol; and transmitting the data unit including the first OFDM symbol and the second OFDM symbol.

Abstract: Method and system method performed at a wireless transmitting station, including generating a first low density parity check (LPDC) codeword for a first source word for a first transmission, and generating a second LDPC codeword for a retransmission for the first LDPC codeword, the second LDPC codeword including a permutated subset of information bits included in the first LDPC codeword and parity check bits corresponding to the permutated subset of information bits.

Abstract: Methods and devices are disclosed for encoding source words and decoding codewords with LDPC matrices, comprising: receiving a 1×K source word row vector ?; and generating a 1×N codeword vector c=?·G, wherein G is a K×N generator matrix derived from a parity check matrix Hl; and wherein Hl is derived from a base parity check matrix H by summing different rows in the base parity check matrix H to obtain an intermediate parity check matrix, and applying a lifting matrix to the intermediate base parity check matrix to obtain Hl.

Abstract: A modulation method, including: modulating data by using a non-uniform constellation; and sending the modulated data. When the non-uniform constellation provided in embodiments of this application is used, for each noise standard deviation, a BER of the non-uniform constellation provided in embodiments of this application is lower than a BER of an existing QAM constellation.

Abstract: An LDPC code encoding method and a communication apparatus are described that provide increased redundant bits through retransmission in an IR-HARQ mechanism, so as to decrease a channel coding rate, and improve decoding performance of an LDPC code. A check matrix of the LDPC code is used as a basic matrix, and the basic matrix is extended to obtain a mother matrix compatible with a plurality of code rates. During LDPC encoding, a transmit device reads, from the mother matrix, a check matrix corresponding to a required code rate, and performs LDPC encoding on an information bit sequence based on the read check matrix. LDPC encoding is performed on the information bit sequence by using check matrices of different sizes, to obtain different quantities of redundant bits.

Abstract: A convolutional code rate matching method and a communication apparatus are provided. A puncturing pattern of a second codeword at a second code rate is obtained based on a puncturing pattern of a first codeword at a first code rate. A second puncturing location set of the second codeword is a subset of a first puncturing location set of the first codeword. When a transmit device decreases a code rate from the first code rate to the second code rate, a redundant bit is sent at a location of a complementary set of the second puncturing location set relative to the first puncturing location set. Compared with the first puncturing location set, the second puncturing location set may obtain more incremental redundant bits, to decrease a channel encoding rate. This can improve decoding performance of a convolutional code.

Abstract: 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.

Abstract: Methods and devices are disclosed for encoding source words and decoding codewords with LDPC matrices, comprising: receiving a 1×K source word row vector ?; and generating a 1×N codeword vector c=?·G, wherein G is a K×N generator matrix derived from a parity check matrix Hl; and wherein Hl is derived from a base parity check matrix H by summing different rows in the base parity check matrix H to obtain an intermediate parity check matrix, and applying a lifting matrix to the intermediate base parity check matrix to obtain Hl.

Abstract: Methods and apparatus for facilitating wireless communication using digital Quadrature Amplitude Modulation are disclosed. A wireless communication device utilizes a signal constellation for quadrature modulating a signal for transmission or quadrature demodulating a received signal. The signal constellation includes multiple constellation symbols and associated bit sequences, which can be translated there between. Specific signal constellations are disclosed.

Abstract: A method for design an optimized constellation set and labeling for satellite point to multi-point transmission systems including transmitters and receivers, wherein the transmitters are adapted to create signals overlay and are configured to allow simultaneous transmission of at least two different data streams (services) intended for users with different radio link qualities. In particular, N services are provided to users having a good radio link and a subset of services is maintained and guaranteed for the users having a lower radio link quality condition.

Abstract: Methods and apparatus for facilitating wireless communication using digital Quadrature Amplitude Modulation are disclosed. A wireless communication device utilizes a signal constellation for quadrature modulating a signal for transmission or quadrature demodulating a received signal. The signal constellation includes multiple constellation symbols and associated bit sequences, which can be translated there between. Specific signal constellations are disclosed.

Abstract: Methods and devices for encoding source words and decoding codewords wherein encoding a source word includes: receiving a 1×K source word row vector ?; and generating a 1×N codeword vector c=?·G, wherein G is a K×N generator matrix derived from a parity check matrix HI; and wherein the parity check matrix HI is derived from a base parity check matrix H by applying an optimized lifting matrix to the base parity check matrix H.

Abstract: Embodiments of the present invention disclose a frame transmission method for a wireless local area network and a wireless local area network apparatus, and relate to the field of communications technologies. According to the present invention, in a frame transmission process in a WLAN, a frame sent by a wireless local area network WLAN apparatus is received, and the frame of a particular standard is recognized by detecting a user common signal field included in the frame, so that backward compatibility of a WLAN apparatus is implemented, and hybrid networking of WLAN apparatuses of different standards can be supported, thereby improving flexibility of network deployment, and reducing complexity of networking.

Abstract: Methods and devices are disclosed for encoding source words and decoding codewords with LDPC matrices. The Methods and devices use a LDPC matrix Hn of lifting factor Z. The LDPC matrix Hn comprises a plurality of submatrices, each submatrix having a size of Z×Z, and at least one submatrix has m1 diagonals of “1” m1 is an integer>=2.

Abstract: A method for design an optimized constellation set and labeling for satellite point to multi-point transmission systems including transmitters and receivers, wherein the transmitters are adapted to create signals overlay and are configured to allow simultaneous transmission of at least two different data streams (services) intended for users with different radio link qualities. In particular, N services are provided to users having a good radio link and a subset of services is maintained and guaranteed for the users having a lower radio link quality condition.

Abstract: Methods and apparatus for facilitating wireless communication using digital Quadrature Amplitude Modulation are disclosed. A wireless communication device utilizes a signal constellation for quadrature modulating a signal for transmission or quadrature demodulating a received signal. The signal constellation includes multiple constellation symbols and associated bit sequences, which can be translated there between. Specific signal constellations are disclosed.

Abstract: Methods and apparatus for facilitating wireless communication using digital Quadrature Amplitude Modulation are disclosed. A mapping module electronic component of a wireless communication device utilizes a signal constellation for quadrature modulating a signal for transmission or quadrature demodulating a received signal. The signal constellation includes multiple constellation symbols and associated bit sequences. Specific signal constellations are disclosed. The signal constellations may be obtained through an optimization procedure which accounts for both phase noise and power amplifier nonlinearity.