Abstract: A data transmission method includes during data retransmission, a first information bit sequence is polar encoded to obtain a first encoded bit sequence, where a first encoding matrix corresponding to the polar encoding includes a part of a first subcode of a polar code and a part of a second subcode of the polar code; and the first encoded bit sequence is sent. Based on the foregoing solution, the first information bit sequence may be encoded by using the first subcode and the second subcode.

Abstract: In an LDPC code-based communication method, through row grouping and column grouping, an LDPC base matrix may be divided into a plurality of units of a same scale. The plurality of units include three types: a first unit, a second unit, and a third unit. A column weight of each column of the first unit is 1. A column weight of at least one column of the second unit is 1, and a column weight of a remaining column is 0. A column weight of each column of the third unit is 0. None of the column weights of the columns of the first unit, the second unit, and the third unit is greater than 1.

Abstract: A polar code construction method and an apparatus. A communication apparatus obtains a reliability weight sequence, and determines a first threshold that indicates a weight of lowest reliability of a subchannel corresponding to an information bit. The communication apparatus determines a non-pre-frozen subchannel corresponding to a content value greater than or equal to the first threshold in the reliability weight sequence as the subchannel corresponding to the information bit based on the first threshold, and performs polar coding on the information bit based on the subchannel corresponding to the information bit.

Abstract: This application provides a bit mapping method and an apparatus. In the method, a first bit sequence is divided into Y sub-blocks, and each sub-block is punctured and/or shortened, so that at least some bits (for example, Ai bits) of each sub-block can be discarded, and the discarded bits are relatively even.

Abstract: A sequence transmission method includes that a sending device determines, based on an information bit sequence, an information column quantity set associated with a base graph and a lifting size set associated with the base graph, where the base graph corresponds to the information bit sequence; determines a target information column quantity and a target lifting size based on the information column quantity set and the lifting size set; and encodes the information bit sequence based on the target information column quantity and the target lifting size, to obtain an encoded bit sequence. The target information column quantity and the target lifting size are determined by comparing X first metrics, and an xth first metric in the X first metrics is determined based on a length of the information bit sequence.

Abstract: An information sending method, an information receiving method, and a related apparatus enable a first communication apparatus to send 1st-stage information and 2nd-stage information, where the 2nd-stage information is generated based on an encoding scheme and/or a segmentation scheme determined according to a first rule. In this way, the 2nd-stage information is transmitted. A first communication apparatus determines the 1st-stage information and the 2nd-stage information that correspond to a same service type, where the 1st-stage information is transmitted on a control channel and/or a shared channel, the 2nd-stage information is transmitted on the shared channel, the 2nd-stage information is generated based on the encoding scheme and/or the segmentation scheme determined according to the first rule.

Abstract: A communication method and apparatus, where the method includes: determining K first bit positions based on a reliability sequence having a length of N1, and determining K second bit positions based on a reliability sequence having a length of N2; determining, based on an information bit sequence having a length of K, A information bits corresponding to X groups of first bit positions, where the X groups of first bit positions include A first bit positions in the K first bit positions; and mapping information bits corresponding to an xth group of first bit positions to an xth group of second bit positions of a first sequence having a length of (N2?N1), to obtain a second sequence, where X groups of second bit positions include A second bit positions in the K second bit positions, and x=1, 2, . . . , X.

Abstract: An encoding method, a decoding method, and an apparatus. A symbol quantity S is determined based on an encoding bit quantity L and an energy level quantity B, where S is S1 or S2, S1=L/B, and S2=L/2B. K information sub-channels are determined from an encoding sequence based on the symbol quantity S, the energy level quantity B, and a reliability sequence. K information bits are encoded and a bit sequence is output based on the K information sub-channels, where the K information sub-channels are selected from candidate sub-channels based on an order of reliability of the candidate sub-channels. The candidate sub-channels are S1 sub-channels or 2×S2 sub-channels in a sub-sequence whose energy level is i in the encoding sequence.

Abstract: A polar code encoding method and an apparatus are provided. The method includes: mapping, based on a reliability sequence whose length is N, an information bit sequence whose length is k to k bits of a first sequence whose length is N, to obtain a second sequence including k information bit positions, x PC bit positions, and N?k?x frozen bit positions; multiplying the second sequence by a first matrix to obtain a third sequence; and performing polar encoding to obtain a fourth sequence, where k?K?N, 1?x, K is a maximum value of the length of the information bit sequence, k, K, N, and x are all positive integers.

Abstract: A modulation method, a demodulation method, and a communication apparatus are provided which relate to the field of communication technologies. The communication apparatus may obtain information bit sequences, divide the information bit sequences into G groups, then separately encode each group of information bit sequences to obtain r encoded bit sequences, map the r encoded bit sequences into a modulation symbol sequence, and output the modulation symbol sequence. The modulation method provided in embodiments of this application may implement a flexible compromise between complexity and robustness, and has a wider range of application.

Abstract: Embodiments of this application disclose a polar code encoding method, a polar code decoding method, and apparatuses thereof, to reduce encoding and decoding complexity. The method in embodiments of this application includes: generating an input vector, where the input vector includes T subblocks, a first information bit of a first subblock is obtained by replicating a second information bit of a second subblock, the first subblock and the second subblock are subblocks of the T subblocks, a sequence number of the first subblock is after a sequence number of the second subblock, and T is an integer greater than or equal to 2; and performing polar encoding on the input vector to obtain an encoded bit.

Abstract: Provided herein is a method and system for managing multiple Access Points (APs) in a wireless network utilizing a multi-dimensional, cluster-based coordination scheme, known as a hybrid scheme. The hybrid scheme harmonizes the frequency and spatial domains to achieve consistent Signal-to-Interference Ratio (SIR) for all Main Access Points (M-AP) and Secondary Access Points (S-AP) Service Stations (STAs). In various implementations, the hybrid scheme may apply specific algorithms for coordinating the M-APs and S-APs.

Abstract: According to a first aspect of the disclosure, methods are discussed in which a station (STA) sends a message to an access point, for example an associated access point, about a change in multi-AP coordination parameters. A STA, which may be a mobile STA, can be in a better position than the APs themselves, for detecting changes in conditions which can affect the effectiveness, or even the desirability of the multi-AP coordination. Accordingly the STA can send a message reporting detected conditions related to multi-AP coordination. In some embodiments, such a message can request for initializing multi-AP coordination, such a message can be in response to a triggering event detected by the STA. In response to such a triggering event, the STA can analyze the STA's service needs, and send the message about a change in multi-AP coordination parameters. A second aspect of the disclosure provides an AP-to-AP negotiation process for multi-AP coordination.

Abstract: A retransmission method includes obtaining, by a sending apparatus, a to-be-encoded bit sequence comprising K to-be-encoded bits, where K is a positive integer. The method also includes performing polar encoding on the to-be-encoded sequence to obtain an encoded first bit sequence. A length of the first bit sequence is N0. The method also includes determining an initial transmission version RV0. The method also includes determining a length E1 of a retransmission version RV1. The method also includes determining the retransmission version RV1 based on an initial transmission code rate RO. The method also includes sending the RV1.

Abstract: A polar encoding and decoding method and apparatus are provided. The method includes: obtaining K to-be-encoded bits; selecting K sequence numbers from a first sequence, where the to-be-encoded bits are placed on polar channels corresponding to the K sequence numbers; and performing polar code encoding on the K to-be-encoded bits to obtain encoded bits, where the first sequence includes sequence numbers of N polar channels, and the first sequence is one or a sub-sequence of a related sequence. This technical solution is applicable to a short message communication system of a BeiDou satellite. The method can effectively improve performance of the communication system and reduce complexity.

Abstract: This application provides a communication method and a related apparatus. A first device obtains a to-be-transmitted bit sequence; 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 modulated symbol. The first device sends the modulated symbol to a second device. Correspondingly, the second device receives the modulated symbol; and demodulates the modulated symbol, to obtain the bit sequence. 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 a first modulation scheme, the first constellation point set is a subset of a second constellation point set, the second constellation point set is a set of a plurality of constellation points corresponding to a predefined second modulation scheme.

Abstract: A communication method and apparatus is provided so that a fading channel can implement a good error correction capability. This helps improve information transmission reliability. The method includes: a transmit end device determines, based on N bit sets, a first sequence and a second sequence that are obtained through quadrature amplitude modulation QAM. The first sequence includes N in-phase components, and the second sequence includes N quadrature components; or the first sequence includes N quadrature components, and the second sequence includes N in-phase components, where N is an integer greater than or equal to 2. Then, the transmit end device performs interleaving processing on the first sequence, to obtain a third sequence. Then, the transmit end device sends, to a receive end device, a symbol sequence determined based on the second sequence and the third sequence. The symbol sequence includes N QAM symbols.

Abstract: This application provides a polar code encoding method and an apparatus. The method includes: determining a threshold based on a length N of a first reliability sequence and a length M of an encoded bit sequence, where N is a positive integer power of 2, and M is a positive integer; determining a first sub-sequence and a second sub-sequence based on a rate matching method of the encoded bit sequence and the first reliability sequence; determining, based on the threshold, the first sub-sequence, the second sub-sequence, the rate matching method of the encoded bit sequence, and the first reliability sequence, K information bits corresponding to the encoded bit sequence, where K is a positive integer less than M; and performing polar encoding to obtain the encoded bit sequence.

Abstract: Reduced numbers of encoded bits obtained by encoding input bits by a polar code are incrementally output, for transmission for example. The polar code comprises bit indices for placing bit values before encoding. The bit indices include a first set of bit indices for placing values of the input bits and a second set of bit indices for placing a predetermined bit value. A first reduced number of the encoded bits start from a first starting position, and a second reduced number of the encoded bits start from a second starting position different from the first starting position. The second reduced number of the encoded bits include one or more of the encoded bits not included in the first reduced number of the encoded bits. The reduced numbers of encoded bits may be output from continuous positions, in a circular buffer for example, or may include repeated bits.

Abstract: A coding method and apparatus are provided. The method includes: coding an information bit by using a preset generator matrix of a systematic (U|U+V)-code to obtain a codeword of a systematic code. The preset generator matrix of the systematic (U|U+V)-code includes a first identity sub-matrix of a U code and a second identity sub-matrix of a V code. A plurality of elements in a same column as the first identity sub-matrix are all 0. A plurality of elements in a same column as the second identity sub-matrix are all 0.