Research On LDPC Channel Encoding And Decoding Technologies In Deep Space Communication

Low-Density Parity-Check (LDPC) codes are a class of capacity approaching error- correcting codes. By using low complexity sum-product algorithm, LDPC codes can get near Shannon limit decoding performance while almost all errors are detectable. Long LDPC codes can even outperform Turbo codes. Now, the application of LDPC has been put on the agenda.Based on features of deep space communication channel,firstly,the representation and construction of LDPC codes are addressed. Secondly, the two decoding algorithm for LDPC codes, i.e., bit-flipping algorithm and sum-product algorithm are discussed. Meanwhile optimization algorithm is proposed. Thirdly,the efficient encoding problem of LDPC codes is discussed in detail. At last, hardware realization of LDPC codes is presented, so that their performances can be validated.Although long LDPC codes are superior to Turbo codes, it is not the case for short LDPC codes. So coding and decoding of LDPC codes need to be researched further. So that the problem of channel transmission of our country's deep space communication can be solved perfectly.