Systems, methods, and instrumentalities are disclosed for interleaving coded bits. A wireless transmit/receive unit (WTRU) may generate a plurality of polar encoded bits using polar encoding. The WTRU may divide the plurality of polar encoded bits into sub-blocks of equal size in a sequential manner. The WTRU may apply sub-block wise interleaving to the sub-blocks using an interleaver pattern. The sub-blocks associated with a subset of the sub-blocks may be interleaved, and sub-blocks associated with another subset of the sub-blocks may not be interleaved. The sub-block wise interleaving may include applying interleaving across the sub-blocks without interleaving bits associated with each of the sub-blocks. The WTRU may concatenate bits from each of the interleaved sub-blocks to generate interleaved bits, and store the interleaved bits associated with the interleaved sub-blocks in a circular buffer. The WTRU may select a plurality of bits for transmission from the interleaved bits.

A node receives transmissions associated with a given set of information bits, wherein each of the transmissions use a different polar code and share one or more information bits of the given set of information bits. The node determines, at each of a plurality of polar decoders of the node, soft information for each information bit included in an associated one of the transmissions, wherein each of the plurality of polar decoders is associated with a different transmission of the transmissions. The node provides, from each polar decoder of the plurality to one or more other polar decoders of the plurality, the determined soft information for any information bits shared by their respective associated transmissions, and uses the provided soft information in an iterative decoding process to decode one or more of the received transmissions.

Systems and methods are disclosed herein for puncturing Polar-encoded bits. In some embodiments, a method of operation of a radio node that utilizes a Polar encoder comprising performing Polar encoding of a plurality of bits to provide a plurality of Polar-encoded code bits and puncturing the plurality of Polar-encoded code bits using a hybrid puncturing scheme to provide a plurality of rate-matched Polar-encoded code bits, wherein the hybrid puncturing scheme uses different puncturing patterns for different code rate regions.

Apparatus and methods are provided for polar code sub-block interleaving and bit selection. In one novel aspect, middle-part interlaced sub-block interleaving is provided for polar code interleaving. In one embodiment, the middle part of the polar code is interlaced and generates the interleaved polar code. In another embodiment, the lower part and the upper part are also sub-block interleaved with the middle-part interlaced method. In another novel, rate-dependent unified bit selection is provided. The bit selection is categorized into three operation categories of repetition, puncturing and the shortening. Each category follows unified bit selection rule with different categories differ only in the access scheme. In one embodiment, the circular buffer is used for bit selection.

Embodiments of this application provide a polar code rate matching method and apparatus, and a communications apparatus. The rate matching method includes: determining N to-be-encoded bits, where the N to-be-encoded bits include N1 information bits, and both N1 and N are positive integers; encoding the N to-be-encoded bits to obtain N encoded bits; obtaining a first puncturing sequence based on an information bit length N1, the quantity N of the encoded bits, and a quantity Q of to-be-punctured bits; and performing a puncturing operation on the N encoded bits based on the first puncturing sequence to implement a rate matching. To-be-punctured bits indicated in the first puncturing sequence are obtained based on the information bit length N1, the quantity N of the encoded bits, and the quantity Q of the to-be-punctured bits, and are not generated randomly.

According to certain embodiments, a transmit node in a wireless communications system includes a first universal rate-compatible polar encoder and a transmitter. The first universal rate-compatible polar encoder is configured for a family of two or more types of channels and encodes a plurality of information bits to provide a plurality of coded bits. The transmitter transmits the plurality of coded bits to a receive node.

A rate matching method including: determining a receiving capability of a receive end, where the receiving capability is used to indicate a maximum data processing volume of the receive end in a first transmission time, and/or the receiving capability is used to indicate a maximum data buffer volume of the receive end in a first transmission time; the first transmission time is used to transmit a first transport block to which a first code block belongs; determining N.sub.CB based on the receiving capability, where N.sub.CB represents a code block size used for rate matching; performing rate matching on the first code block based on N.sub.CB. The receive end can adjust, based on a processing capability and/or a buffer capability that are/is of the receive end in a period of time, the code block size used for rate de-matching, to avoid insufficiency in processing capability and/or buffer overflow at the receive end.

A communication apparatus includes: an encoder that encodes an input vector to output a codeword of polar code; a memory that stores a reliability-ordered sequence of indices of the input vector and a set of indices for rate-matching; a controller that is configured to: select a frozen set of indices based on at least one of a universal rate-matching scheme and the reliability-ordered sequence stored in the memory such that the reliability-ordered sequence is generated without considering the rate-matching scheme; construct the input vector by setting the frozen set to a frozen bit and a non-frozen set to information bits; and skip codebits of the codeword outputted by the encoder from transmission, the codebits corresponding respectively to the set of indices for rate-matching.

A node receives transmissions associated with a given set of information bits, wherein each of the transmissions use a different polar code and share one or more information bits of the given set of information bits. The node determines, at each of a plurality of polar decoders of the node, soft information for each information bit included in an associated one of the transmissions, wherein each of the plurality of polar decoders is associated with a different transmission of the transmissions. The node provides, from each polar decoder of the plurality to one or more other polar decoders of the plurality, the determined soft information for any information bits shared by their respective associated transmissions, and uses the provided soft information in an iterative decoding process to decode one or more of the received transmissions.

Methods and devices for puncturing of a polar code in a wireless network, wherein nested puncturing sets are determined based on a puncturing order which is determined based on a reliability order of information bit channels, so that only one index sequence needs to be stored for both the determination of the information set and the determination of the punctured set and so that puncturing does not require to adjust the information set at error prone indexes corresponding to puncturing indexes. The puncturing order might start with indexes corresponding to high reliability bit channels or to low reliability bit channels.