LDPC码的和积算法，码长可以任意，输出多项式即可，译码输出软信息-Sum-product algorithm for LDPC codes, code length can be arbitrary, the output polynomials can be, decoder outputs soft information

harq is used for error correction and to decode the errors while transmit

FEC编码源程序，对HARQ纠错有一定的帮助-FEC source coding, HARQ error correction help

程序先进行卷积编码，然后进行viterbi译码，程序有纠错功能，中间出现误码，程序解码时会自动纠正-Convolution coding program first and then viterbi decoding program has error correction, the error appears in the middle, when the program will automatically correct decoding