Research On Construction Method Of Non-binary QC-LDPC Codes Based On Extended Field

The high demand of human beings for communication rate and call quality has continuously promoted the rapid development of mobile communication technology.In order to meet the requirements of ultra-high speed,high reliability and low delay transmission of data,the research of channel coding and decoding technology has practical significance.LDPC code is a Shannon limit progressive codes.With the increasing attention of LDPC codes in the field of channel coding,many researchers also conduct in-depth research and Discussion on the encoding and decoding scheme of LDPC codes and the construction method of check matrix.In the face of more diversified use occasions and higher technical indicators in modern communication,modern channel coding technology,as the core technology in mobile communication system,has also ushered in new challenges.This paper takes the basic knowledge of channel coding as the starting point.Firstly,through the basic principle of channel coding and various channel coding technologies,this paper introduces the research focus of this paper,LDPC codes encoding and decoding algorithm,and then discusses the basic definition,representation and composition of LDPC codes in turn.Secondly,the paper gives a block based design method for the construction of quasi cyclic LDPC codes,and designs a specific check matrix for this method.Secondly,this paper gives a block design method for the construction of quasi cyclic LDPC codes,and designs a specific check matrix for this method.Then,based on the existing research,this paper puts forward an improved scheme on the basic structure of BIBD QC-LDPC codes,and theoretically analyzes and proves the feasibility of the improvement.It is concluded that the advantage of QC-LDPC codes is that it is not only simple to code,but also easy to implement in hardware.Finally,through the analysis of QC-LDPC coding,we can know the coding characteristics of nonbinary QC-LDPC(nb-qc-ldpc)codes based on extended domain.Nonbinary QC-LDPC codes not only has quasi cyclic characteristics,but also has excellent performance of multi-level.Finally,we carry out in-depth research on nonbinary QC-LDPC codes.The main innovations and work contents of this paper include the following aspects:(1)The related construction methods of the specific extended domain are studied.According to the existence theorem of the extended domain,the specific extended domain construction methods and construction examples are given.Through programming,the primitive polynomials and primitives on the ternary domain are obtained,and finally the powers on the primitives are calculated,which lays a knowledge foundation for the subsequent coding and decoding of nonbinary QC-LDPC codes.(2)Aiming at the high construction complexity of nonbinary QC-LDPC codes,this paper studies the construction method of nonbinary QC-LDPC codes based on extended field GF(3 ^ m).On the basis of the specific extended field construction method given above,combined with the coding method of nonbinary QC-LDPC codes,the construction process of check matrix H in coding is improved,which makes the coding simpler and better performance.(3)For the decoding of nonbinary QC-LDPC codes,this paper puts forward the idea of combining traditional binary BP decoding with nonbinary QC-LDPC codes.During the iterative update of decoding,the whole coding and decoding process of nonbinary QC-LDPC codes on extended field GF(3 ^ m)is realized by modifying the value limited range of variable nodes.Finally,the simulation shows that the nonbinary QC-LDPC codes constructed based on the extended field given in this paper has the advantages of simple structure,excellent performance The combination of high efficiency and BP decoding improves the coding efficiency and accuracy.