1. A block code decoding method, comprising the steps of: (A) systematically encoding a first information code is systematically encoded to generate a first block code comprising the first information code and a first parity check code; (B) transmitting the first block code; (C) receiving the first block code to be a first received block code comprising a first received information code corresponding to the first information code; (D) establishing a plurality of exclusive-or (XOR) mask vectors based on the dimension k of the first information code and a selected Hamming distance of p, wherein the dimension of each of the plurality of XOR mask vectors is k, the plurality of XOR mask vectors are a combination of permuted mask vectors, each of which has k components with 0˜p components therein having a value of i and the other components therein having a value of j, and each of the permuted mask vector corresponds to a permutation of the k components; (E) proceeding an XOR calculation with the first received information code and the plurality of XOR mask vectors and obtaining a plurality of second information codes; (F) encoding the plurality of second information codes and obtaining a plurality of second block codes; and (G) proceeding a correlation calculation with the first received code and the plurality of second block codes.