A Rate Compatible Coding Method Based on Feedback Block Markov Superposition Coding

Abstract

The invention belongs to the field of digital communication and digital storage, and relates to a rate-compatible coding method based on feedback packet Markov superposition coding. First, the information sequence with a length of kL u Divide into L equal-length groups u =( u (0) , u (1) ,…, u (L‑1) ), the length of each packet is k; for time t=-1,-2,...,-m and i=1,2,...,N, the length is n i sequence of ‑k w (i,t) The initialization is set as an all-zero sequence; at t=0,1,...,L‑1, the sequence with length k is sent to the system code C respectively i [n i ,k]’s checksum generator to encode and get a length of p i =n i ‑k checksum sequence combined with w (i,t‑1) , w (i,t‑2) ,..., w (i,t‑m) Calculate codeword c The tth subsequence of c (t) ;At time t=L, L+1,...,L+T-1, the all-zero sequence of length k u (t) = 0 respectively sent to the system code C i [n i ,k]’s checksum generator to encode and get a length of p i =n i check sequence for ‑k s (i,t) = 0 , and compute the subsequence c (t) , the subsequence c (t) The check part of is used as the code word c The tth subsequence of . The invention has the advantages of simple encoding, approachable channel capacity, unified encoding structure and low complexity.

Description

technical field [0001] The invention belongs to the field of digital communication and digital storage, in particular to a rate-compatible coding method based on feedback packet Markov superposition coding. Background technique [0002] Problems such as multi-network coexistence and high-speed mobility make the quality of the communication channel time-varying, that is, the noise level of the channel varies at different times. In order to ensure the reliability of data transmission in time-varying communication systems, it is necessary to design channel codes that can approach the channel capacity and have a variable code rate, that is, rate-compatible codes that can approach the capacity. In 1948, Shannon proposed the famous channel coding theorem. Since then, people have been devoting themselves to the design and construction of channel codes that approach or reach channel capacity. In 1993, Berrou et al. proposed Turbo code, which opened the era of modern coding based o...

AI Technical Summary

Problems solved by technology

However, as the memory length increases, the decoding delay and decoding complexity of block Markov superposition coding will increase significantly

Therefore, the non-recursive block Markov superposition coding method is not suitable for time-varying communication systems with limited decoding energy consumption

On the other hand, the rate-compatible encoding method based on non-recursive block Markov superposition coding has the following problem: when the code rate changes, the encoding memory length required by the rate-compatible code based on non-recursive block Markov superposition coding will also change

Therefore, the encoder and decoder of this type of rate-compatible code do not have a unified structure, which will greatly increase the complexity of hardware implementation of this type of code, making it impossible to apply to time-varying communication systems with limited hardware resources

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