210results about "Error correction/detection using LDPC codes" patented technology

Methods, systems, and devices for wireless communications are described. A wireless communication device may implement a low-density parity-check (LDPC) code to encode and / or decode bits of a signal. The LDPC code may be defined by a base graph and a lifting scheme. The base graph may include check nodes and variable nodes. The lifting scheme may define a quantity of copies of the base graph used to generate the LDPC code and respective cyclic shifts associated with connected variable nodes and check nodes. The respective cycle shifts may be defined such that one or more cycles associated with a minimum length of the LDPC code are associated with a restriction on second degree variable nodes, nodes associated with least significant bits, or a combination thereof. Additionally, or alternatively, the respective cycle shifts may be defined such that a weighted girth of the LDPC code satisfies a threshold.

Methods, systems, and devices for wireless communications are described. A user equipment (UE) may transmit an indication to a network entity that the UE is capable of decoding Reed-Solomon codes and that the UE is capable of performing near maximal likelihood demodulation. The network entity may transmit a message indicating that a Reed-Solomon code is applied to one or more scheduled signals based at least in part on the indication. The network entity may apply Reed-Solomon coding to a signal of the one or more scheduled signals based at least in part on the message. The UE may apply near maximal likelihood demodulation and Reed-Solomon decoding to a received signal of the one or more scheduled signals based at least in part on the message.

A method and apparatus for receiving a PPDU in a wireless LAN system are provided. Specifically, a receiving STA receives a PPDU from a transmitting STA via a first frequency band and decodes the PPDU. The PPDU includes a preamble and a data field. The first frequency band includes a first sub-block and a second sub-block. The data field includes first data for the first sub-block and second data for the second sub-block. The first data is generated based on data in which constellation mapping is performed on coded data bits. The second data is generated based on data obtained by replicating the first data and applying phase rotation to the data.

A communication method and a communication device based on LDPC code may perform encoding or decoding based on a storage matrix and indication information, the indication information may include first information, and each of a plurality of row pairs indicated by the first information includes two rows, a set composed of the column numbers of the columns where the non-zero elements in the first x elements of the first row in the two rows are located is a proper subset of a set composed of the column numbers of the columns where the non-zero elements in the first x elements of the second row in the two rows are located, and therefore splitting expansion is achieved in the low-code-rate expansion process. In other words, the first row can be eliminated on the basis of adding the second row, so that the orthogonality between the rows is improved. Moreover, the plurality of first rows indicated by the first information can form one or more row groups, and the first rows included in each row group have an association relationship, so that the orthogonality can be further improved based on the association relationship. Therefore, the orthogonality between rows can be improved, and the decoding performance can be improved.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive a reference signal for estimation of at least one parameter associated with generation of an adapted low density parity check (LDPC) graph. The UE may transmit an indication of an adapted LDPC graph that is based on at least one adaptation metric associated with the at least one parameter. The UE may receive, based on the adapted LDPC graph, a downlink shared channel communication. Numerous other aspects are described.

Systems and methods for processing bit-interleaved coded modulation (BICM) signals from a BICM transmitter to generate information bit estimates of information in the BICM signals, including a decoder to generate the information bit estimates of the information in the received BICM signals and a symbol a posteriori probability (APP) generator to generate first symbol a posteriori probabilities (APPs) by processing the BICM signals based on Euclidean distances derived from the BICM signals, and further based on symbol probability log-likelihood ratios (SPLLRs) provided to the symbol APP generator by an extrinsic-information-based symbol probability log-likelihood ratio (SPLLR) generator. The SPLLR generator generates the SPLLRs directly from extrinsic information based on updated symbol APPs output from the decoder, without converting the extrinsic information into log-likelihoods (LLs), and the decoder generates the information bit estimates based on the first symbol APPs output from the symbol APP generator.

Disclosed is a method comprising, by a transmitter apparatus, partitioning (901) an input data stream to obtain a bit stream X1 and a bit stream X2; subjecting (902) the bit stream X2 to encoding by LDPC encoders, to obtain X2 parity bits, and X2 information bits; applying (903) SPC encoding to the X2 parity bits, together with the bit stream X1, to obtain sign bits, wherein the bit stream X1 is used as padding bits; subjecting (904) the sign bits, the padding bits, and the X2 information bits, to an interleaver operation to obtain an interleaver output; subjecting (905) the interleaver output to Gray mapping to form multiple consecutive quadratic amplitude modulation, QAM, symbols; modulating (905) the QAM symbols by quadratic amplitude modulation to obtain a modulated data stream; and transmitting (906) the modulated data stream via a radio access network or optical fibre communication network.

Methods, apparatuses, and computer readable media for signaling with unequal and finer MCSs, where an apparatus of an AP is configured to: encode a user field for a MU MIMO allocation, the user field comprising a station (STA) identification (ID) (STA-ID) subfield, a modulation and coding scheme (MCS) subfield, a spatial configuration subfield, and a Low-Density Parity Check (LDPC) subfield, the STA-ID subfield identifying a STA associated with the AP. The wireless devices are configured for signaling unequal and finer MCSs, modulation patterns, 2×LDPC, and 1×LDPC.

A transmitter is provided that shapes uniformly-distributed bits into a non-uniformly distributed bits according to a parity check matrix of a linear code such that a product of the parity check matrix and the non-uniformly distributed bits equals the uniformly-distributed bits. Similarly, receiver is provided that recovers the uniformly-distributed bits from the non-uniformly distributed bits through a multiplication of the non-uniformly-distributed bits with the parity check matrix.

The present disclosure provides a system and a method for implementing rate recovery in the PUSCH and PDCH bit rate processing chain of network. The system packs log likelihood ratios (LLRs) data in such a way that for each equalized in phase and quadrature (IQ) symbols, a predetermined number of LLRs equal to the modulation order are packed. The system de-interleaves the packed LLRs by reading the most significant bit (MSB) LLRs row wise for the number of columns equal to the modulation order. The system uses a single buffer for de-interleaving, bit-deselection, and filler bit addition stages, thereby reducing memory requirement of the system. The system processes only a predetermined number of LLRs to a HARQ combining stage to optimize memory and reduce latency.

A transmitter is provided that shapes uniformly-distributed bits into a non-uniformly distributed bits according to a parity check matrix of a linear code such that a product of the parity check matrix and the non-uniformly distributed bits equals the uniformly-distributed bits. Similarly, receiver is provided that recovers the uniformly-distributed bits from the non-uniformly distributed bits through a multiplication of the non-uniformly-distributed bits with the parity check matrix.

Provided is a method (300) and a successive interference cancellation (SIC) based multi-user uplink receiver (200) for multi-user uplink transmission. The method comprises receiving (302) signal of one or more multiple-access (MA) scheme waveforms by a plurality of antennas (202.1, . . . , 202.R) from one or more users. The method further comprises determining (304) one or more effective channel matrices corresponding to the plurality of antennas. Thereby, the method comprises performing (306) channel equalization for signal received in a corresponding antenna by an effective channel matrix. Furthermore, the method comprises combining (308) the channel equalized signal. Subsequently, the method comprises detecting (310) Correctly Decoded Code Blocks (CCBs) and Wrongly Decoded Code Blocks (WCBs). Upon detecting CCBs and WCBs, the method comprises performing (312) the SIC on received signals from one or more users until all WCBs are converted to CCBs or a maximum number of threshold iterations are completed.

To secure favorable communication quality in data transmission using an LDPC code.SOLUTION: In group-wise interleaving, the LDPC code with a code length N of 69120 bits is interleaved in units of 360-bit bit groups. In group-wise deinterleaving, a sequence of the LDPC code after group-wise interleaving is returned to an original sequence. The present technology can be applied, for example, to a case of performing LDPC code-based data transmission and the like.SELECTED DRAWING: Figure 185

A method and a device for wireless communication are described. The method comprising segmenting a payload (305) into a plurality of code blocks, generating, for each code block, a cyclic redundancy check, CRC, associating the CRC generated for each code block with each respective code block, performing low density parity check code, LDPCC, encoding of each code block and associated CRC to generate one or more codewords of a plurality of codewords and transmitting the codewords generated by performing the LDPCC encoding.

To secure favorable communication quality in data transmission using an LDPC code.SOLUTION: In group-wise interleaving, the LDPC code with a code length N of 69120 bits is interleaved in units of 360-bit bit groups. In group-wise deinterleaving, a sequence of the LDPC code after group-wise interleaving is returned to an original sequence. The present technology can be applied, for example, to a case of performing LDPC code-based data transmission and the like.SELECTED DRAWING: Figure 172

An LDPC code-based communication method and a communication apparatus are provided. There is a nested relationship between base graphs, so that a base graph of a small scale can be derived based on a base graph of a large scale. The communication apparatus may store a base graph of a largest scale. When another base graph needs to be used for encoding or decoding, the communication apparatus may derive a required base graph based on the base graph of the largest scale. In this way, content that needs to be stored by the communication apparatus can be reduced.

An encoder outputs a first bit sequence having N bits. A mapper generates a first complex signal s1 and a second complex signal s2 with use of bit sequence having X+Y bits included in an input second bit sequence, where X indicates the number of bits used to generate the first complex signal s1, and Y indicates the number of bits used to generate the second complex signal s2. A bit length adjuster is provided after the encoder, and performs bit length adjustment on the first bit sequence such that the second bit sequence has a bit length that is a multiple of X+Y, and outputs the first bit sequence after the bit length adjustment as the second bit sequence. As a result, a problem between a codeword length of a block code and the number of bits necessary to perform mapping by a set of modulation schemes is solved.

In one embodiment, a first codeword is generated by error correction encoding a first individual payload, and a second codeword is generated based on bits associated with a second individual payload, the bits interleaving with bits associated with the first individual payload. Another embodiment includes encoding individual payloads by, for example, low density parity check (LDPC) encoding to generate encoded bits, the encoded bits including a first encoded bit generated by encoding a first individual payload, and a second encoded bit generated by encoding a second individual payload, where the encoded bits include a first encoded bit generated by encoding the first individual payload, and a second encoded bit generated by encoding the second individual payload, where the encoded bits include a first encoded bit generated by encoding the first individual payload, and a second encoded bit generated by encoding the second individual payload. The bits associated with the first individual payload are combined with the second individual payload. The first codeword and the second codeword each include encoded bits based on bits associated with the first individual payload. The first codeword in these embodiments may be decoded independently of the second codeword, and may also be decoded in conjunction with the second codeword.

The invention provides a mode for constructing the LDPC basis matrix, the LDPC basis matrix can be obtained according to the storage matrix and the indication information used for indicating the corresponding relation between the rows of the storage matrix or the expected corresponding relation between the rows of the LDPC basis matrix, and in the process of obtaining the LDPC basis matrix, the LDPC basis matrix can be obtained according to the indication information. And the number of the total edges on the Tanner graph corresponding to the non-expanded columns is not changed. Therefore, through the mode provided by the invention, the calculation complexity of the LDPC code can be maintained, and particularly, the calculation complexity of the low-code-rate LDPC code can be reduced and the decoding efficiency can be improved in a scene of expanding from a high code rate to a low code rate.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive a reference signal for estimation of at least one parameter associated with generation of an adapted low density parity check (LDPC) graph. The UE may transmit an indication of an adapted LDPC graph that is based on at least one adaptation metric associated with the at least one parameter. The UE may receive, based on the adapted LDPC graph, a downlink shared channel communication. Numerous other aspects are described.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a low density parity check (LDPC) code may include a parity check matrix (PCM) with a lifted parity submatrix. The lifted parity submatrix may include an upper-triangular portion having non-zero diagonal elements, a high-degree column portion, an all-zero portion, and a remaining portion, resulting in improved encoding efficiency. In some aspects, a transmitter may encode, in a first encoding operation, the upper-triangular portion and the high-degree column portion, and the transmitter may encode, in a second encoding operation, the all-zero portion and the remaining portion of the lifted parity submatrix. The encoded lifted parity submatrix may be transmitted from the transmitter to a receiver in a PCM as part of an LDPC code. Additionally, a base graph PCM structure may be included in the remaining portion of the lifted parity submatrix. Numerous other aspects are described.

An apparatus for generating broadcast signal frame according to an embodiment of the present invention includes a combiner configured to generate a multiplexed signal by combining a core layer signal and an enhanced layer signal; a power normalizer configured to reduce power of the multiplexed signal to a power level corresponding to the core layer signal; a time interleaver configured to generate a time-interleaved signal by performing time-interleaving that is applied to both the core layer signal and the enhanced layer signal; and a frame builder configured to generate a broadcast signal frame including a preamble for signaling start position information and size information for each of Physical Layer Pipes (PLPs). In this case, the Physical Layer Pipes include a core layer physical layer pipe corresponding to the core layer signal and an enhanced layer physical layer pipe corresponding to the enhanced layer signal.

The invention provides a communication method and a related device. The complexity of geometric forming can be reduced. The method comprises the following steps: a first device obtains a bit sequence to be transmitted, and modulates the bit sequence based on a third modulation scheme to map the bit sequence to each constellation point in a third constellation point set to obtain a modulation symbol; and the first device sends the modulation symbol to the second device, and correspondingly, the second device receives the modulation symbol and demodulates the modulation symbol to obtain the bit sequence. Wherein a plurality of constellation points in the third constellation point set are non-uniformly distributed, the third constellation point set is similar to a first constellation point set corresponding to the first modulation scheme, the first constellation point set is a subset of a second constellation point set, and the second constellation point set is a set of a plurality of constellation points corresponding to a predefined second modulation scheme; the order of the second modulation scheme is higher than that of the first modulation scheme, and the order of the third modulation scheme is the same as that of the first modulation scheme.

The invention relates to a system and a method for a quasi-cyclic low density parity check (QC-LDPC) code with a 1 / 2 code rate. An apparatus may include a transmitter and one or more processors. The one or more processors may be configured to identify a first binary parity check matrix for a quasi-cyclic low density parity check (QC-LDPC) code according to a code rate of 1 / 2 and a code block size of 7776 bits, the first binary parity check matrix corresponding to a first exponential matrix. The one or more processors may be configured to encode data using the first binary parity check matrix. The transmitter may be configured to transmit the encoded data.

To secure favorable communication quality in data transmission using an LDPC code.SOLUTION: In group-wise interleaving, the LDPC code with a code length N of 69120 bits is interleaved in units of 360-bit bit groups. In group-wise deinterleaving, a sequence of the LDPC code after group-wise interleaving is returned to an original sequence. The present technology can be applied, for example, to a case of performing LDPC code-based data transmission and the like.SELECTED DRAWING: Figure 143

Methods, systems, and devices for wireless communications are described. The described techniques may enable a transmitting device to perform probabilistic shaping using an energy function that is independent of a modulation and coding scheme (MCS) used by the transmitting device. For example, the transmitting device may encode a set of information bits according to a probability distribution, the energy function, a symbol alphabet, and a shaping parameter. The transmitting device may generate a set of probabilities corresponding to the symbol alphabet based on an energy sequence computed using the energy function, where a quantity of terms in the energy sequence may be based on a shaping order. The transmitting device may indicate the shaping order to a receiving device.

The invention discloses a coding method and device and a decoding method and device. A sending end acquires a first bit sequence, performs LDPC coding on the first bit sequence based on a check matrix to obtain a second bit sequence, and outputs the second bit sequence. Correspondingly, the receiving end receives the to-be-decoded information of the second bit sequence, LDPC decoding is carried out on the to-be-decoded information of the second bit sequence based on the check matrix, and K1 information bits are obtained. Wherein the check matrix is determined based on the corresponding relation of the first information columns and the first base graph, and the column number of the first information columns is determined based on the number K1 of the information bits and the column number K of the information columns of the first base graph. According to the technical scheme provided by the invention, the code rate can be effectively improved.

An apparatus and method for multiplexing signals using layered division multiplexing are disclosed. A signal multiplexing apparatus according to an embodiment of the present invention includes a combiner configured to combine a core layer signal and an enhanced layer signal at different power levels, and a time interleaver configured to perform interleaving applied to both the core layer signal and the enhanced layer signal.