Channel encoding method and apparatus
A channel encoding method and apparatus. The method includes: obtaining A to-be-encoded information bits; mapping the A to-be-encoded information bits and L CRC bits to a first bit sequence based on an interleaving sequence, where the L CRC bits are obtained based on the A to-be-encoded information bits and a CRC polynomial, the interleaving sequence is obtained from a prestored interleaving sequence table or is obtained based on a maximum-length interleaving sequence, A+L is less than or equal to Kmax, and Kmax is a length of the maximum-length interleaving sequence; and encoding the first bit sequence. In this way, not only an encoding delay can be reduced, but also decoding has an early stop capability, so that decoding can end in advance, thereby reducing a decoding delay.
1. A channel decoding method comprising:
obtaining to-be-decoded bits, wherein the to-be-decoded bits comprise A information bits and L cyclic redundancy check (CRC) bits; and
performing channel decoding on the to-be-decoded bits, wherein the channel decoding comprises de-interleaving with an interleaving sequence and a CRC check operation with a CRC polynomial, the interleaving sequence is obtained from a prestored interleaving sequence table based on a value of A and not based on CRC data, and, in the interleaving sequence table, each information bit length corresponds uniquely to one and only one interleaving sequence.
2. The channel decoding method according to claim 1 , wherein the deinterleaving further comprises:
determining positions of the A information bits and the L CRC bits.
3. The channel decoding method according to claim 2 , wherein determining the positions of the A information bits and the L CRC bits further comprises:
identifying a correspondence that is between at least one CRC bit and at least one information bit and that corresponds to A from a prestored table of correspondences between the L CRC bits and the A information bits, wherein the correspondence between at least one CRC bit and at least one information bit indicates all information bits checked by using each of the L CRC bits, the correspondence between the at least one CRC bit and the at least one information bit is obtained based on an information bit length and the CRC polynomial, and the CRC check operation is based on the correspondence.
4. The channel decoding method according to claim 1 , wherein, when A=32, the interleaving sequence in the prestored interleaving sequence table is:
0, 2, 3, 5, 7, 10, 11, 12, 14, 15, 18, 19, 21, 24, 26, 30, 31, 32, 1, 4, 6, 8, 13, 16, 20, 22, 25, 27, 33, 9, 17, 23, 28, 34, 29, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, wherein 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, and 55 are indexes of CRC bits.
5. A channel decoding apparatus, comprising:
a memory configured to store a program instruction; and
a processor configured to execute the program instruction to:
obtain to-be-decoded bits, wherein the to-be-decoded bits comprise A information bits and L cyclic redundancy check (CRC) bits; and
perform channel decoding on the to-be-decoded bits, wherein the channel decoding comprises de-interleaving with an interleaving sequence and a CRC check operation with a CRC polynomial, the interleaving sequence is obtained from a prestored interleaving sequence table based on a value of A and not based on CRC data, and, in the interleaving sequence table, each information bit length corresponds uniquely to one and only one interleaving sequence.
6. The channel decoding apparatus according to claim 5 , wherein the deinterleaving further comprises:
determining positions of the A information bits and the L CRC bits.
7. The channel decoding apparatus according to claim 6 , wherein determining the positions of the A information bits and the L CRC bits further comprises:
identifying a correspondence that is between at least one CRC bit and at least one information bit and that corresponds to A from a prestored table of correspondences between the L CRC bits and the A information bits, wherein the correspondence between the at least one CRC bit and the at least one information bit indicates all information bits checked by using each of the L CRC bits, the correspondence between the at least one CRC bit and the at least one information bit is obtained based on an information bit length and the CRC polynomial, and the CRC check operation is based on the correspondence.
8. The channel decoding apparatus according to claim 5 , wherein, when A=32, the interleaving sequence in the prestored interleaving sequence table is:
0, 2, 3, 5, 7, 10, 11, 12, 14, 15, 18, 19, 21, 24, 26, 30, 31, 32, 1, 4, 6, 8, 13, 16, 20, 22, 25, 27, 33, 9, 17, 23, 28, 34, 29, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, wherein 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, and 55 are indexes of CRC bits.
9. The channel decoding apparatus according to claim 5 , wherein the apparatus is a chip, a terminal device, or a network device.
10. A non-transitory computer-readable storage medium embodying computer program code that, when executed by a channel decoding apparatus, is configured to configure the channel decoding apparatus to:
obtain to-be-decoded bits, wherein the to-be-decoded bits comprise A information bits and L cyclic redundancy check (CRC) bits; and
perform channel decoding on the to-be-decoded bits, wherein the channel decoding comprises de-interleaving with an interleaving sequence and a CRC check operation with a CRC polynomial, the interleaving sequence is obtained from a prestored interleaving sequence table based on a value of A and not based on CRC data, and, in the interleaving sequence table, each information bit length corresponds uniquely to one and only one interleaving sequence.
11. The non-transitory computer-readable storage medium according to claim 10 , wherein the deinterleaving further comprises:
determining positions of the A information bits and the L CRC bits.
12. The non-transitory computer-readable storage medium according to claim 11 , wherein determining the positions of the A information bits and the L CRC bits further comprises:
identifying a correspondence that is between at least one CRC bit and at least one information bit and that corresponds to A from a prestored table of correspondences between the L CRC bits and the A information bits, wherein the correspondence between the at least one CRC bit and the at least one information bit indicates all information bits checked by using each of the L CRC bits, and the correspondence between the at least one CRC bit and the at least one information bit is obtained based on an information bit length and the CRC polynomial, and the CRC check operation is based on the correspondence.
13. The non-transitory computer-readable storage medium according to claim 10 , wherein, when A=32, the interleaving sequence in the prestored interleaving sequence table is:
0, 2, 3, 5, 7, 10, 11, 12, 14, 15, 18, 19, 21, 24, 26, 30, 31, 32, 1, 4, 6, 8, 13, 16, 20, 22, 25, 27, 33, 9, 17, 23, 28, 34, 29, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, wherein 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, and 55 are indexes of CRC bits.