Polar code rate matching method and polar code rate matching apparatus
Embodiments of the present invention provide a polar code rate matching method and a polar code rate matching apparatus. The method includes: performing matrix-based BRO interleaving on a non-systematic polar code output by a polar code encoder, to obtain interleaved bits; and determining, based on the interleaved bits, a rate-matched output sequence. According to the embodiments of the present invention, matrix-based BRO interleaving is performed on a non-systematic polar code, to obtain a rate-matched output sequence, so that a sequence structure after interleaving is more random, which can reduce an FER, thereby improving HARQ performance and ensuring reliability of data transmission.
1. A polar code rate matching method, comprising:
performing, by a rate matching apparatus, matrix-based bit reversal order (BRO) interleaving on a non-systematic polar code output by a polar code encoder, to obtain interleaved bits;
determining, by the rate matching apparatus, based on the interleaved bits, a rate-matched output sequence;
transmitting, by the rate matching apparatus, the rate-matched output sequence;
wherein performing matrix-based BRO interleaving on the non-systematic polar code output by the polar code encoder, to obtain interleaved bits comprises:
writing, by the rate matching apparatus, bits of the non-systematic polar code by row, to form a first matrix of M 1 rows×M 2 columns, wherein M 1 and M 2 are positive integers;
performing, by the rate matching apparatus, a first substitution operation on a column of the first matrix to obtain a second matrix, wherein the first substitution operation is a BRO operation with a size of M 2 ;
performing, by the rate matching apparatus, a second substitution operation on a row of the second matrix to obtain a third matrix, wherein the second substitution operation is a BRO operation with a size of M 1 ;
reading, by the rate matching apparatus, bits according to a column of the third matrix, and using the bits as the interleaved bits;
or
writing, by the rate matching apparatus, bits of the non-systematic polar code by column to form a first matrix of M 1 rows×M 2 columns, wherein M 1 and M 2 are positive integers;
performing, by the rate matching apparatus, a first substitution operation on a column of the first matrix to obtain a second matrix, wherein the first substitution operation is a BRO operation with a size of M 2 ;
performing, by the rate matching apparatus, a second substitution operation on a row of the second matrix to obtain a third matrix, wherein the second substitution operation is a BRO operation with a size of M 1 ; and
reading, by the rate matching apparatus, bits, according to a row of the third matrix, and using the bits as the interleaved bits.
2. A polar code rate matching method, comprising:
dividing, by a rate matching apparatus, a systematic polar code output by a polar code encoder into system bits and parity check bits;
performing, by the rate matching apparatus, matrix-based bit reversal order (BRO) interleaving on the system bits to obtain a first group of interleaved bits;
performing, by the rate matching apparatus, matrix-based BRO interleaving on the parity check bits to obtain a second group of interleaved bits;
determining, by the rate matching apparatus, based on the first group of interleaved bits and the second group of interleaved bits, a rate-matched output sequence;
wherein performing matrix-based BRO interleaving on the system bits to obtain a first group of interleaved bits comprises:
writing, by the rate matching apparatus, the system bits by row to form a first matrix of M 1 rows×M 2 columns;
performing, by the rate matching apparatus, a first substitution operation on a column of the first matrix to obtain a second matrix, wherein the first substitution operation is a BRO operation with a size of M 2 ;
performing, by the rate matching apparatus, a second substitution operation on a row of the second matrix to obtain a third matrix, wherein the second substitution operation is a BRO operation with a size of M 1 , and
reading, by the rate matching apparatus, bits according to a column of the third matrix, and using, by the rate matching apparatus, the bits as the first group of interleaved bits, wherein M 1 and M 2 are positive integers;
or
writing, by the rate matching apparatus, the system bits by column to form a first matrix of M 1 rows×M 2 columns;
performing, by the rate matching apparatus, a first substitution operation on a column of the first matrix to obtain a second matrix, wherein the first substitution operation is a BRO operation with a size of M 2 ;
performing, by the rate matching apparatus, a second substitution operation on a row of the second matrix to obtain a third matrix, wherein the second substitution operation is a BRO operation with a size of M 1 ;
reading, by the rate matching apparatus, bits according to a row of the third matrix; and
using, by the rate matching apparatus, the bits as the first group of interleaved bits, wherein M 1 and M 2 are positive integers.
3. The method according to claim 2 , wherein performing matrix-based BRO interleaving on the parity check bits to obtain a second group of interleaved bits comprises:
writing, by the rate matching apparatus, the parity check bits by row to form a first matrix of M 1 rows×M 2 columns;
performing, by the rate matching apparatus, a first substitution operation on a column of the first matrix to obtain a second matrix, wherein the first substitution operation is a BRO operation with a size of M 2 ;
performing, by the rate matching apparatus, a second substitution operation on a row of the second matrix to obtain a third matrix, wherein the second substitution operation is a BRO operation with a size of M 1 ;
reading, by the rate matching apparatus, bits according to a column of the third matrix, and using the bits as the second group of interleaved bits, wherein M 1 and M 2 are positive integers; or
writing, by the rate matching apparatus, the parity check bits by column to form a first matrix of M 1 rows×M 2 columns;
performing, by the rate matching apparatus, a first substitution operation on a column of the first matrix to obtain a second matrix, wherein the first substitution operation is a BRO operation with a size of M 2 ;
performing, by the rate matching apparatus, a second substitution operation on a row of the second matrix to obtain a third matrix, wherein the second substitution operation is a BRO operation with a size of M 1 ; and
reading, by the rate matching apparatus, bits according to a row of the third matrix, and using the bits as the second group of interleaved bits, wherein M 1 and M 2 are positive integers.
4. A polar code rate matching apparatus, comprising:
a non-transitory memory configured to store instructions; and
a processor coupled to the memory and configured to execute the instructions stored in the memory to cause the apparatus to:
perform matrix-based bit reversal order (BRO) interleaving on a non-systematic polar code output by a polar code encoder, to obtain interleaved bits,
determine, based on the interleaved bits, a rate-matched output sequence,
write bits of the non-systematic polar code by row to form a first matrix of M 1 rows×M 2 columns, wherein M 1 and M 2 are positive integers,
perform a first substitution operation on a column of the first matrix to obtain a second matrix, wherein the first substitution operation is a BRO operation of M 2 bits,
perform a second substitution operation on a row of the second matrix to obtain a third matrix, wherein the second substitution operation is a BRO operation of M 1 bits, and
read bits according to a column of the third matrix; or
write bits of the non-systematic polar code by column to faun a first matrix of M 1 rows×M 2 columns, wherein M 1 and M 2 are positive integers,
perform a first substitution operation on a column of the first matrix to obtain a second matrix, wherein the first substitution operation is a BRO operation of M 2 bits,
perform a second substitution operation on a row of the second matrix to obtain a third matrix, wherein the second substitution operation is a BRO operation of M 1 bits, and
read bits according to a row of the third matrix.
5. A rate matching apparatus, comprising:
a non-transitory memory configured to store instructions; and
a processor coupled to the memory and configured to execute the instructions stored in the memory to cause the apparatus to:
divide a systematic polar code output by a polar code encoder into system bits and parity check bits,
perform matrix-based bit reversal order (BRO) interleaving on the system bits to obtain a first group of interleaved bits, and perform matrix-based BRO interleaving on the parity check bits to obtain a second group of interleaved bits,
determine, based on the first group of interleaved bits and the second group of interleaved bits, a rate-matched output sequence,
write to-be-interleaved bits by row to form a first matrix of M 1 rows×M 2 columns, wherein M 1 and M 2 are positive integers,
perform a first substitution operation on a column of the first matrix to obtain a second matrix, wherein the first substitution operation is a BRO operation of M 2 bits,
perform a second substitution operation on a row of the second matrix to obtain a third matrix, wherein the second substitution operation is a BRO operation of M 1 bits, and
read bits according to a column of the third matrix; or
write to-be-interleaved bits by column to form a first matrix of M 1 rows×M 2 columns, wherein M 1 and M 2 are positive integers,
perform a first substitution operation on a column of the first matrix to obtain a second matrix, wherein the first substitution operation is a BRO operation of M 2 bits,
perform a second substitution on a row of the second matrix to obtain a third matrix, wherein the second substitution operation is a BRO operation of M 1 bits, and
read bits according to a row of the third matrix.