Certain aspects of the present disclosure generally relate to wireless communications and, more particularly, to methods and apparatus for rate-matching control channels using polar codes. An exemplary method generally includes encoding a stream of bits using a polar code, determining a size of a circular buffer for storing the encoded stream of bits based, at least in part, on a minimum supported code rate and a control information size, and performing rate-matching on stored encoded stream of bits based, at least in part, on a mother code size, N, and a number of coded bits for transmission, E.

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.

A method in a node (110, 115) comprises generating (604) a plurality of constituent polar codes, each of the plurality of constituent polar codes having an associated block length and an associated set of information bits. The method comprises coupling (608) at least a portion of the sets of information bits associated with each of the plurality of constituent polar codes to generate a spatially coupled polar code. The method comprises encoding (612) a wireless transmission using the spatially coupled polar code.

A polar code encoding method and apparatus, the method including determining a sorted sequence to encode to-be-encoded bits, where the sorted sequence represents reliability sorting of N polar channels, where N is a mother code length of a polar code, where N is a positive integer, where N is a power of two, and where a minimum sequence number of polar channels in the sorted sequence is 1, obtaining encoded bits by the apparatus by performing polar code encoding on the to-be-encoded bits using the sorted sequence, and outputting, by the apparatus, the encoded bits.

A polar code encoding method and apparatus, the method including determining a sorted sequence to encode to-be-encoded bits, where the sorted sequence represents reliability sorting of N polar channels, where N is a mother code length of a polar code, where N is a positive integer, where N is a power of two, and where a minimum sequence number of polar channels in the sorted sequence is 1, obtaining encoded bits by the apparatus by performing polar code encoding on the to-be-encoded bits using the sorted sequence, and outputting, by the apparatus, the encoded bits.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a wireless communication device may determine to block puncture or to block shorten a set of transmitted bits of an adjusted fractally enhanced kernel polar code for a communication of an incremental redundancy (IR)-hybrid automatic repeat request (HARQ) process based at least in part on a code rate associated with the communication of the IR-HARQ process. The wireless communication device may generate the adjusted fractally enhanced kernel polar code for the communication based at least in part on determining to block puncture or to block shorten the set of transmitted bits. The wireless communication device may transmit the communication using the adjusted fractally enhanced kernel polar code. Numerous other aspects are provided.

A polar code encoding method and apparatus are provided, to improve accuracy of reliability sorting of polar channels. The method is: determining a sorted sequence used to encode to-be-encoded bits, where the sorted sequence is used to represent reliability sorting of N polar channels, N is a mother code length of a polar code, and N is a positive integer power of 2; and performing polar code encoding on the to-be-encoded bits by using the sorted sequence, to obtain encoded bits.

Embodiments of this application provide a method and an apparatus for constructing a coding sequence. The method includes: storing a reliability sequence corresponding to a basic sequence, where a length of the reliability sequence corresponding to the basic sequence is less than or equal to a length of a reliability sequence corresponding to a mother code sequence; storing a reliability reference sequence, where the reliability reference sequence includes at least one element remaining after the reliability sequence corresponding to the basic sequence is excluded from the reliability sequence corresponding to the mother code sequence; and constructing a coding sequence by using the reliability sequence corresponding to the basic sequence and an element in the reliability reference sequence. During implementation of this application, during storage, only the reliability sequence corresponding to the basic sequence and the reliability reference sequence are stored. Because a sum of the length of the reliability sequence corresponding to the basic sequence and a length of the reliability reference sequence is far less than the length of the original reliability sequence, storage overheads can be reduced.

Embodiments of this application provide a method and an apparatus for constructing a coding sequence. The method includes: storing a reliability sequence corresponding to a basic sequence, where a length of the reliability sequence corresponding to the basic sequence is less than or equal to a length of a reliability sequence corresponding to a mother code sequence; storing a reliability reference sequence, where the reliability reference sequence includes at least one element remaining after the reliability sequence corresponding to the basic sequence is excluded from the reliability sequence corresponding to the mother code sequence; and constructing a coding sequence by using the reliability sequence corresponding to the basic sequence and an element in the reliability reference sequence. During implementation of this application, during storage, only the reliability sequence corresponding to the basic sequence and the reliability reference sequence are stored. Because a sum of the length of the reliability sequence corresponding to the basic sequence and a length of the reliability reference sequence is far less than the length of the original reliability sequence, storage overheads can be reduced.

A polar code encoding method and apparatus are provided, to improve accuracy of reliability sorting of polar channels. The method is: determining a sorted sequence used to encode to-be-encoded bits, where the sorted sequence is used to represent reliability sorting of N polar channels, N is a mother code length of a polar code, and N is a positive integer power of 2; and performing polar code encoding on the to-be-encoded bits by using the sorted sequence, to obtain encoded bits.