The Design And High Efficiency Decoding Algorithm Of Low-density Parity-check Codes In High Speed Data Transmission System

The informationization battlefield will face the massive data information transmission and procession in the future,the demand for broadband wireless high-speed data transmission has become increasingly urgent.As a vital part of high-speed data transmission systems,channel coding technology can correct the transmitted information with low SNR and limited bandwidth,which can save transmitter power,overcome channel adverse effects,improve information data transmission efficiency,decoding performance,and increase communication reliability while improving spectrum utilization.Therefore,this technology has an extremely important impact on information transmission efficiency and channel capacity.Low-density parity check codes,as one of the most superior codes in channel coding,its decoding algorithm can realize parallel operation and it has the potential of high-speed decoding,the theoretical analysis and engineering application of this code have made important progress internationally.At present,the code has been widely used in optical communication,deep space communication,high-speed data transmission system and fifth-generation mobile communication.However,there are still some unsolved problems in the theoretical research and engineering implementation of LDPC codes.At present,there have the following challenges: 1)In order to achieve the better coding gain and decoding performance,the code length is usually selected as long as possible.If the code length is long,the storage and wires of the check node and the variable node occupy a large amount of resources,and the computation complexity for check nodes will also be very high,and it is difficult to meet the requirements of real-time decoding.2)There is still a certain theoretical bottleneck in the analysis of code performance,that is,how to construct a good code with superior performance from the principle still needs further exploration.Based on the above problems,this paper mainly carried out the following aspects:1.A construction method of LDPC code is explored.This topic is devoted to the construction method based on the finite field.Based on the existing work,a method of constructing LDPC code based on computer search is proposed.The LDPC code check matrix constructed by this method is extremely regular,which is beneficial to the solution and storage of the generator matrix;and is superior to the standard code performance recommended by the US Space Data Committee.2.We introduce how to solve the generator matrix based on the constructed LDPC code.This paper introduces how to obtain the generator matrix based on the LDPC code proposed in this paper,and introduces the existing mainstream LDPC encoder.3.Based on the LDPC code constructed in this paper,considering its extremely regular structure,a decoding algorithm which can reduce the complexity of hardware implementation is proposed.Based on matrix transform,two decoding algorithms have been proposed by matrix transforming,which can improve the decoding performance.