In the communication process

due to the interference of the channel

the information be erroneous.Error correction code is usually used to improve the accuracy of the transmitted data. Concatenated codes as a kind of error correction codes are widely used due to their excellent performance

and LDPC codes are increasingly used as a good code that is close to the Shannon limit. Therefore

the research on LDPC codec algorithms has become a hot topic This dissertation takes the LDPC code in forward error correction system of DVB-S2 protocol as the research background

and introduces the minimum sum algorithm

offset minimum sum algorithm and normalized minimum sum algorithm of LDPC code decoding. In this paper

a minimum sum algorithm implementation method is proposed

and it is used to the implementation of normalized minimum sum algorithm and the offset minimum sum algorithm. After comparing the number of iterations and the error rate

the offset parameter is set to 0.1 and the number of iterations is set to 20

and the algorithm is used as the optimal algorithm to implement the LDPC decoder design.