Decoding Method and Device, and Decoder

A decoder, comprising:

• a receiver, the receiver configured to receive N log-likelihood ratios (LLRs) corresponding to a to-be-decoded signal, wherein N is a code length;
• at least one memory, the at least one memory configured to store a program instruction, an LLR table, a partial sum, a decoding result, a decoding path queue, and a path metric PM value queue, wherein the partial sum is an input of a G function;
• and
• at least one processor, the at least one processor configured to control program instruction execution, wherein the at least one processor is configured to:
• classify K decoded bits into reliable bits and unreliable bits based on at least one of a prior LLR or a posterior LLR, wherein the prior LLR is an average LLR that is of a decoded bit and that is obtained based on channel statistical information, and the posterior LLR is an LLR that is of a decoded bit and that is calculated in real time based on the N LLRs;
• generate M decoding paths based on the N LLRs and a preset rule, wherein 1≤M≤Q, Q is a preset total quantity of decoding paths, a total quantity of paths at each stage does not exceed L, L is a preset total quantity of decoding paths with a same length, and L≤Q, and wherein the preset rule is that:
• there is one next-stage path for the reliable bits and two next-stage paths for the unreliable bits, a decoding path with a path length of j consists of decision results of a first to a jth decoded bits, and each decision result corresponds to one stage of the decoding path K is a final quantity of decoded bits N, M, Q, L, K, and j are all positive integers, and 1≤j≤N;
• and
• select each stage of target decoding path based on path metric (PM) values of the M decoding paths to obtain a decoding result of each stage of decoded bit;
• when a length of a first decoding path reaches N, perform cyclic redundancy check (CRC) on K decoded bits in the first decoding path;
• and at least one of:
• return a decoding success if the CRC succeeds;
• or
• continue to perform CRC on K decoded bits in a next decoding path whose length reaches N, and return a decoding failure if a result of performing the CRC on K decoded bits in each decoding path whose length reaches N is that the CRC fails.