Rate matching method and apparatus for polar code

An apparatus for rate matching for a Polar code, comprising:

• a processor;
• and
• a non-transitory memory with instructions thereon, wherein the instructions upon execution by the processor cause the processor to:
• generate a bit sequence of N bits from K information bits and (N−K) frozen bits, and encode the bit sequence of N bits by means of a Polar code encoder with a generator matrix of size N×N to generate an initial bit sequence {S0, S1, . . . , SN−1} of N bits, wherein K and N are both positive integers and K is less than or equal to N;
• select bits from the initial bit sequence {S0, S1, . . . , SN−1} in a non-repeated manner and write the bits into a circular buffer;
• and
• generate a bit sequence to be transmitted of a specified length from the bits in the circular buffer based on a predefined starting position in the circular buffer,
• wherein the writing the bits into the circular buffer comprises writing the bits into the circular buffer based on a predefined rule, wherein the predefined rule is determined by a one-to-one mapping interleaving function f(n) generated according to a data characteristic of the Polar code, wherein n=0, 1, . . . , N−1, f(n)=0, 1, . . . , N−1, n is a bit position index in the initial bit sequence, and f(n) is a position index in the circular buffer, and
• wherein, in response to a code rate that is less than or equal to a predefined threshold, a position of P0=N−M in the circular buffer is taken as the predefined starting position, wherein P0 represents a position index of the bit sequence in the circular buffer, M is a length of the bit sequence to be transmitted, and N is a length of the initial bit sequence.

A computer-readable storage medium comprising instructions which, when executed by a computing system, cause the computing system to carry out a method, comprising:

• generating a bit sequence of N bits from K information bits and (N−K) frozen bits, and encoding the bit sequence of N bits by means of a Polar code encoder with a generator matrix of size N×N to generate an initial bit sequence {S0, S1, . . . , SN−1} of N bits, wherein K and N are both positive integers and K is less than or equal to N;
• selecting bits from the initial bit sequence {S0, S1, . . . , SN−1} in a non-repeated manner and writing the bits into a circular buffer;
• and
• generating a bit sequence to be transmitted of a specified length from the bits in the circular buffer based on a predefined starting position in the circular buffer,
• wherein the writing the bits into the circular buffer comprises writing the bits into the circular buffer based on a predefined rule, wherein the predefined rule is determined by a one-to-one mapping interleaving function f(n) generated according to a data characteristic of the Polar code, wherein n=0, 1, . . . , N−1, f(n)=0, 1, . . . , N−1, n is a bit position index in the initial bit sequence, and f(n) is a position index in the circular buffer, and
• wherein, in response to a code rate that is less than or equal to a predefined threshold, a position of P0=N−M in the circular buffer is taken as the predefined starting position, wherein P0 represents a position index of the bit sequence in the circular buffer, M is a length of the bit sequence to be transmitted, and N is a length of the initial bit sequence.